摘要:

J O U R N A L A. J. ALLMAND M. C. D. Sc. A. W. CROSSLEY C.M.G. C.B.E. SIR JAMES J. DOBBIE MA. D.Sc. M. 0. FORSTEH D.Sc. Ph.D. F.R.S. T. A. HENRY D.Sc. J. T. HEWITT M.A. D.Sc. Ph.D. D. Sc. F. R. S. F. R. S. F. R. R. OF C. A. KEANE D.Sc. Ph.D. H. R. LESUEUR D.Sc. T. M. LOWRP C.B.E. D.Sc. F.R.S. J. I. 0. MASSON M.B.E. D.Sc. G. T. MORGAN O.B.E. .D.Sc. J. C. PHILIP O.B.E. D.Sc. Ph.D. A. SCOTT M.A. D.Sc. F.R.S. F.R.S. THE CHEMICAL SOCIETY 2Jb%fl G. BARGER M.A. D.Sc. F.R.S. H. M. DAWSON Ph.D. D.Sc. J. C. DRUMMOND D.Sc. W. GODDEN B.Sc. J . KENNER D.Sc. Ph.D. S. I. LEVY B.A. B.Sc. W. S. MILLAR M.A. B.Sc. P1i.D. G. F. MORRELL Ph.D. D.Sc. J. R. PARTINGTON M.B.E. D.Sc. T. S. PATTERSON D.Sc. Ph.D. T. H. POPE B.Sc. T. SLATER PRICE D.Sc. Ph.D. Etms E. H. RODD D.Sc. W. P. SKERTCHLY. F. SODDY M.A. F.R.S. J. F. SPENCER D.Sc. Ph.D. L. J. SPENCER M.A. R. V. STANFORD M.Sc. Ph.D. D. F. TWISS D.Sc. A. JAMIESON WALKER Ph. D. B. A. J. C. WITHERS Ph.D. H. WREN M.A. D.Sc. Ph.D. S. S. ZILVA D.Sc. Ph.D. 1920. Vol. CXVIII. Part I. LONDON GURNEY drr JACKSON 33 PATERNOSTER ROW E.C. 4. 1 920.Abstractors of the Journal of the Society of Cheinical Industry who have contributed to this volume. S. S. AUSTIN. J. F. BRIGGS. T. H. BURNHAM. L. EYNON. A. J. HALL. J. H. JOHNSTON M.Sc. J. H. LANE. C. A. MITCBELL M.A. J. P. OGILVIE. A. R. POWELL. W. E. I?. POWNEY. W. H. SCHOELLER Ph.D. A. B. SEARLE. J. 8. G. THOMAS B.SC. D. WOODRUFFE W. J. WBIWT PRINTED IN GREAT BRITAIN BY RICHARD CLAY & SONS LIMITED PBRIS GARWN8 STAMFORD ST. S.E 1 AND BYNC+AYI SUFFOLK.

ISSN:0368-1769    

DOI:10.1039/CA92018FP001

出版商:RSC    

年代:1920

数据来源: RSC

摘要:

J O U R N A L A. W. CROSSLEY C.M.G. C.B.E. SIR JAMES J. DOBBIE M.A. D.Sc. &I. 0. FORPTER D.&. Ph.D. F.R.S. T. A. HENRY D. Sc. J. T. HEWITT M.A. D.Sc. Ph.D. D.Sc. F.R.S. F.R.S. F.R.S. OF H. R. LE SUEUR D.Sc. T. M. LOWRY C.B.E. D.Sc. F.R.S. J. I. 0. MASSON M.B.E. D.Sc. G. T. MORGAN O.B.E D.Sc. J. C. PHILIP O.B.E. D.Sc. Ph.D. A. SCOTT M.A. D.Sc. F.R.S. F.R.S. THE CHEMICAL SOCIETY G. BAROER M.A. D.Sc. F.R.S. H. M. DAWSON Ph.D. D.Sc. J. 0. DRUMMOND D.Sc. W. GODDEN B.Sc. J. KENNER D.Sc. Ph.D. S.I. LEVY B.A. B.Sc. W. S. MILLAR M.A. B.Sc. Ph.D. G. F. MoRRELL Ph.D. D.Sc. J. R. PARTINGTON M.B.E. D.Sc. T. S. PATTERSON D.Sc. Ph.D. T. H. POPE B.Sc. T. SLATER PRICE D.Sc. Ph.D. ABSTRACTS O F PAPERS PHYSICAL INORGANIC MINERALOGICAL ANALYTICAL CHEMISTRY. ON AND E. H. RODD D.Sc. W. P. SKERTCHLY. F. SODDY M.A. F.R.S. J. F. SPENCER D.Sc. Ph.D. L. J. SPENCER M.A. R. V. STANFORD M.Sc. Ph.D. D. F. Twrss D.Sc. A. JAMIESON WALKER Ph.D. B.A J. C. WITHERS Ph.D. H. WREN M.A. D.So. Ph.D. S. 5. ZILVA D.Sc. Ph.D. 1920. Vol. CXVIII. Part 11. LONDON GURNEY L JACKSON 33 PATERNOSTER ROW E.C.4. 1920.Abstractors of the Journal of the Society of Chemical Industry who have contributed to this volume. S. 8. AUSTIN. J. F. BRIGGS. T. H. BURNHAM. L. EYNON. A. J. HALL. J. H. JOHNSTOX MAC. J. H. LANE. C. A. MITOBELL M.A. J. P. OQILYIE. A. R. POWELL. W. E. F. POWNEY. W. R. SOHOBLLER Ph.D. A. B. QEARLE. J. S. G. THOMAS B.Sc. D. WOODRUFFE. W. J. WRIGHT. PRITTED IN GREAT BRITAIN BY RICHARD CLAY & $UNS LIMITED PARIB GARDEN SPAIGfJRD 6T.s 8.R. 1 AND BCNQAV SUFFOLL

ISSN:0368-1769    

DOI:10.1039/CA92018FP003

出版商:RSC    

年代:1920

数据来源: RSC

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ii. 28 ABSTRACTS OF CHEMICAL PAPERS. Inorganic Chemistry. Preparation and Testing of Hydrogen of a High Degree of Purity. J u ~ r u s DAVID EDWARDS (J. Ind. Eng. C h m . 1919 11 961-963).-An apparatus has been devised as a substitute for the Kipp generator. It consists of two connected cylinders into one of which the zinc is introduced whilst a tube through a rubber cork in the bottom is connected with the acid flask. The outlet tube has a side connexion which dips into mercury and serves as a pressure indicator and as a safety valve. Air is exhausted from the cylin-INORGANIC CHEMISTRY. ii. 29 ders the acid flask nearly filled with dilute sulphuric acid and a few fragments of zinc introduced to sweep out the air before the flask is attached to the cylinders. The acid is drawn up into the gsnerator by turning a tap a t the top and opening a vent in the stopper of the acid flask.Pure hydrogen is thus a t once obtained and fresh acid introduced without admitting air. Tests made in c6mparison with pure electrolytic hydrogen by means of the inter- ferometer (A 1315 ii 478) showed that hydrogen produced by this apparatus contained less than 1 part in 10,000 of impurities. I n similar tests of the gas produced by a Kipp generator 83'86% of hydrogen was found to be present seventeen minutes and 99*377L fGI'ty-tWO minutes after starting. [See also J. Soc. Chem. Id. 1920 19A.1 C. A. M. New Experiment to Demonstrate the Minute Mass of a Hydrogen Atom. FR. B ~ ~ R K I (Helv. Chim. Acta 1919 2 703-704).--A yellowish-green fluorescence is distinctly observable in a darkened room when a beam of light is passed through 0.5 C.C.of a solution prepared by dissolving 0.4 mg. of fluorescein in 10 litres of water. The total quantity of hydrogen which can be furnished by the weight of fluorescein present in this solution is 6 x 10-11 grams which therefore gives an upper limit for the mass of the hydrogen atom. The figure is greatly in excess of the gener- ally accepted value. H. W. Composition of the Atmosphere. AUGUST KROGH (Math. fysiske illeddelelser 1919 1 No. 12 1-13).-Our knowledge of the composition of the atmosphere is still quite uncertain especially in regard to hydrogen and the relation between oxygen and nitro- gen. Until very recently little attention has been paid to the varia- tion in the mixture composing the atmosphere at different altitudes.Wsgener claims that a t a height of 70 km. hydrogen must be the chief constituent of the earth's atmosphere. Benedict has shown by 200 analyses extending over a period of nine months that the percentage of oxygen a t the surface or laboratory level never varied more than kO.01 from the average and that of carbon dioxide never more than *0*005. The author describes a new gas analysis appaiatus with three gas burettes one for moving the air sample to and from the absorption pipettes and for saturating the air with moistwe a second convenient in size for measuring the air before and after the ahsorption of carbon dioxide and a third which holds the residual gas after the absorption of oxygen. The author dis- cusses general means for reaching mare accurate and constant results.The heated platinum wire method has been applied for the detection of combustible gases and the conclusion is drawn that hydrogen or other combustible gas is present in an amount which is probably less than 0.002%. The percentage of carbon dioxide in the streets of Copenhagen is usually increased by 0.001-0.007. The need of a thorough research to establish the absolute average com- position of pure atmospheric air with more certainty and a studyii. 30 ABSTRACTS OF CHEMICAL PAPERS. of its variatious especially iii the higher strata of the atmosphere is strongly urged. Accurate analyses of samples taken simultane- ously from aeroplanes a t various heights up to 5 or 6 km. would give valuable inforniat,ion in regard to mixing by vertical currents.Automatic sampling by balloons is suggested. U p to the present time the absolute composition of atmospheric air a t the earth's surface has been found t o be CO 0'030%; N 79.022%; and 0,. 20.948%. CHEMICAL ABSTRACTS. Nitrogen Generator for Laboratory Use. W. L. BADGER (./. 1n.d. Lng. C!/ieni. 1919 11 1052-1053).-A widenecked 2-litre bottle is closed with a rubber stopper through which passes one end of a Liebig condenser jacket (without the condenser tube) ; the lower water-inlet is sealed off and the upper one is connected wit,h a side- tube which extends through the stopper to the bottom of the bottle. A bulb with delivery tube is sealed on the upper end of the jacket. The boltle is packed with copper wire and as much animon(a (1 1) saturated with ammonium chloride is poured in as the bottle will hold.'The jacket is filled with copper turn- ings. Air is blown in through a tube reaching nearly to the bottom of the bottle; the oxygen is absorbed rapidly and practically pure nitrogel? escapes from the delivery tube. The passage of the air (or nitrogen) causes the solution to circulate slowly up the jacket and through the side-tube into the bottle again. w. P. s. The Synthesis of Ammonia at Very High Pressures. GEORGES CLAUDE (Compt. rend. 1919 169 1039-1041).-Having previously shown the possibility of using very high pressures for industrial purposes (ibid. 649) the aut,hor has studied the synthesis of ammonia a t these high pressures and finds that a t a pressure of 1000 kilos./cni.2 and a t a temperature of 5 3 6 O the yield of ammonia is over 40%.The zone of temperature within which this reaction takes place a t a reasonable velocity under such a high pressure is 500-700'. W. G. Behaviour of the Hydronitrogens [Nitrogen Hydrides] and their Derivatives in Liquid Ammonia. VI. Electro- lytic Nitridation of Various Anodes in a Solution of Ammonium Trinitride. A. W. BROWNE M. E. HOLMES and J. S . KING ( J . Anaer. Chem. S O C . 1919 41 1769-1776. Compare A. 1911 ii 1084 1085; 1913 ii 583).-Solutions of 1 gram of ammonium a i d e in 36 C.C. of liquid ammonia were electrolysed a t - 67O using anodes of copper silver cadmium aluminium lead antimony iron and nickel. The gas evolved a t both anode and cathode was measured and the loss of weight of the anode deter- mined. It is shown t h a t copper anodes undergo electrolytic corro- sion to an extent indicating the formation of some cuprous azide CuN with cupric azide CuN as the main product.No gas was liberated a t the anode. With silver. cadmium lead and antimony anodes the corrosion resulted in the formation of normal azides,INORGANIC CHEMISTRY. ii. 31 AgN CdN PbN and SbK9 without liberation of gas a t tlie anode. Aluminium iron and nickel anodes undergo corrosion accompanied by the liberation of nitrogen. The aluminiuni anode became coated with a bulky pyrophoric scale of varying colour and texture. Deep red ferric azide FeN was obtained in solution when a n iron anode was employed but this product was ammono- lysed and yielded an ammono-basic ferric azide.A pink deposit was formed on the nickel anode presumably an ammono-basic nickel azide. J. F. S. Some Properties of Nitrogen Trioxide Pure or in Solution in Nitrogen Peroxide. GEORGES BAUME and MARIUS HOBERT (Compt. rend. 1919 169 968-970).-The authors have studied the melting-point and vapour-pressure diagrams of the system nitrogen trioxide-nitrogen peroxide. The melting-point diagram is normal and has a single eutectic in the 'neighbourhood of the freezing point of pure nitrogen trioxide. From the vapour-pressure curves between -80c and 3 5 O the author deduces the b. p. of pure nitrogen trioxide to be - 2 F / 7 6 0 nun. Pure nitrogen trioxide can only exist a t very low temperatures in the solid state or in the liquid state under pressure of nitric oxide.At temperatures above - l O O c it dissociates. It is not possible to distil it in a vacuum because of the immediate formation of an atmosphere of nitric oxide a t temperatures a t which distillation is possible. W. G . Silicon Hydrides. VII. Protosiloxane O:SiH,. ALFRED STOCK and KARL SOMIESKI (Ber. 1919 52 [R] 1851-1860. Com- pare A 1918 ii lll).-In the earlier paper it was shown t h a t di- bromomonosilane reacts with water to form polymerides of protosil- oxane 0:SiH2. The unimolecular form has now been obtained as a gas by the action of the required amount of water vapour on dichloro- inoiiosilane in a very large Aask under greatly reduced pressure. It has a n extraordinary tendency to polymerise much more so than the analogous carbon compound formaldehyde in consequence of which the flask must be perfectly clean and smooth.Liquid and solid polymerides are formed immediately on condensation. The liquid ones are like benzene and can be obtained conveniently as a solu- tion by shaking a benzene solution of dichloroinonosilane with water. These benzene solutions are fairly stable towards water but reduce silver nitrate in the cold. They correspond roughly with (SiH,?),. The solid polymerides are insoluble. All the polymerides react with sodium hydroxide according to the equation SiH,O + 2NaOH = Na,SiO + 2I-I,. Constitutional Formulae of Kaolinite and other Silicates. RUDOLF WEGSCHEIDER (Zebtsch. Elektrochem. 1919 25 352).-It is shown t h a t the constitutional formulz of polysilicates must be wiitten with the silicon atoms joined through oxygen and not directly with one another.Compounds with the silicon atoms directly united are reducing agents and unstable. Further if the polysili- J. C. W.ij. 32 ABSTRACTS OF CHEMICAL PAPERS. cates are considered as having the silicon atoms directly united it will follow that the oxygen atoms must also be directly united which again will point t o instability. The combination of a strongly reducing group -Si-Si- with a strongly oxidising group -0-0- will of necessity give a compound of an extremely unstable charac- ter which is certainly not the case with the polysilicates. [See also Simmonds T. 1904 85 681; Pukall A . 1910 ii 780; Manchot A. 1910 ii 1060.1 Theory of Binary Mixtures. V. Vapour Pressure and Molecular Constitution of Liquid Argon and Argon-Nitrogen Mixtures.F. UOLBZALEK (Zeztsch. physzkal. Chem. 1919 93 585-595. Compare A. 1916 ii 132).-A theoretical paper in which using the experimental data previously published the asso- ciation constants are calculated from the saturation pressure of the mixture and also the molecular constitution of the mixtures and pure argon the saturation pressures of the liquid mixtures and the constitution of the rapour. It is shown that liquid argon .is partly composed of diatomic molecules and has an association con- stant a t 85’11O abs. of 11=0*20. Hence a t low temperatures argon possesses chemical affinity and consequently argon compounds are to be expected a t low temperatures. There is therefore no funda- mental difference between the inactive gases and other gases but only a difference of degree. When liquid argon is diluted with liquid nitrogen the diatomic molecules dissociate according to the law of mass action.The vapour tension of liquid argon-nitrogen mixtures as well as the constitution of the vapour may be calcu- lated a t all concentrations by means of the author’s theory of solution (A. 1909 ii 2 2 ) . J. F. S. J. F. S. Preparation of Metallic Potassium. FRITZ C. WICKEL and WALTER LOEBEL (D.R.-P. 307175; from Chem. Zentr. 1919 iv 361). -Accurately measured quantities of metallic sodium and potassium hydroxide are melted together with exclusion of air so that sodium oxide is formed and potassium is volatilised from the mixture (at about 670°) and suitably condensed.Hydrogen is obtained as by-product. The process is suitable for the manufacturing scale. H. W. The Autoxidation of Sodamide. HANS SCHHADER (Zeitsch. anorg. Chem. 1919 108 44-48).-The amides of the alkali metals are known to undergo autoxidation with the formation of nitrite hydroxide and ammonia. When finely divided sodamide is exposed to air in presence of a little water a’ yellowish-red oxida- tion product is formed which is now shown to be a peroxide probably of the formula NaNH,,O,. The peroxide formed was estimated by adding the product to a cold saturated solution of barium chloride when barium peroxide was precipitated and was estimated in the usual way It was found that a sample of sodamide gave in fifty-eight days a t ordinary temperature 0.44INORQANIU CHEMISTRY. ii.33 mol. % peroxide and 6.9% nitrite. I n dry air autoxidation does not take place a t the ordinary temperature but a t looo to llOo the peroxide is slowly formed. The peroxide is stable in dry air but in moist air is changed into a white substance the aqueous solution of which gives the peroxide reaction. Solubility and Fusion Relations at High Temperatures and Pressures. GEORGE W. MORBY ( J . Eng. Club Philadelphia 1919 35 509-519).-An address. The preparation of the com- pounds monopotassium aluminate K,O,Al,O large octahedral crystals and monopotassium ferrite KoO,Feo_Os large red octa- hedral crystals decomposed by water below 500° is mentioned. E. H. R. CHEMICAL ABSTRACTS. The Properties of Ammonium Nitrate. I. The Freezing REGINALD GEORGE EARLY Point and Transition-temperatures .and THOMAS MARTIN LOWRY (T. 1919 115 1387-1404). Action of Bromine on Calcium Carbide. EDWARD BARNES (Chem. News 1919 119 260-261).-Liquid bromine acts slowly on calcium carbide a t ordinary temperatures producing carbon hexabromide and calcium bromide. 4.5 Grams of finely powdered calcium carbide treated with 45 grams of purified dry bromine in a 50 C.C. bottle for five months gave a product which after removal of excess of bromine weighed 32.4 grams and contained 2 2 grams of hexabromoethane 8.8 grams of calcium bromide and 0.2 gram of unchanged calcium carbide. Calcium carbide and bromine heated in sealed tubes a t looo until no further action was apparent produced carbon and calcium bromide. Dry chlorine was found to have no action on calcium carbide exposed to it a t the ordinary temperature for two months.S. 8. A. Reduction of Barium Nitrate by the Alternating Current. P. WENGER and A. LUBOMIRSKI (Ann. Chim. anal. 1919 [ii] 1 339-342) .-With lead electrodes the yield of nitrite increases with the amperage but with mercury electrodes the maximum yield is obtained with 0'6 ampere ; the yield also increases with temperature in the case of lead electrodes and decreases with aluminium or zinc electrodes. Temperature has little if any effect when copper cadmium or magnesium electrodes are employed. The oxygen liberated from the nitrate combines with the electrode forming suboxides (copper mercury cadmium and tin electrodes) hydr- oxides (lead zinc aluminium and magnesium electrodes) or oxides (nickel and silver electrodes).The nitrate is not reduced by the Conditions in which Periclase or Crystalline Magnesia is Formed. J . MEUNIER (Bull. SOC. chim. 1919 [iv] 25 560-562).-Magnesium oxide may be freed from contained calcium by igniting the material a t a red heat and metallic electrodes unless the current is passing. w. P. s. Purification of Magnesia VOL. oxvm. ii. 2ii. 34 ABSTRACTS OF CHEMICAL PAPERS. subsequently after cooling extracting it with successive quantities of a 10% sucrose solution until the last extract does not give any turbidity with ammonium oxalate. If such material is then washed with water dissolved in hydrochloric acid the solution evaporated to dryness and the residue gradually heated in a covered crucible until it attains a red heat magnesium oxide is obtained in the form of crystals of periclase on the lid and sides of the crucible and on the surface of the amorphous oxide in the crucible.The material so obtained is very pure. Concentrated Thallium Amalgams their Electro- chemical and Thermochemical Behaviour ; Densities and Freezing Points. THEODORE W. RICHARDS and FARRINGTON DANIELS ( J . Amer. Chem. SOC. 1919 41 1732-1768).-The electromotive force density specific volume specific heat heat of dilution and freezing point of thallium amalgams up to a Concentration of 40‘9% thallium have been experimentally determined. The heat of solu- tion of thallium in mercury and in various amalgams has also been determined. The E.M.F. measurements were made a t 20° 30° and 40° and are shown to be much greater than demanded by the simple concentration law.The temperature-coefficients of the E.M.F.’s have been calculated for the various amalgams and they are found to be less than is demanded by the gas law and vary as the concentration increases. The solution volume of thallium is remarkably constant varying only from 17.47 to 17.51 but it is somewhat larger than the specific volume (17.21) of thallium. Thallium therefore must expand on amalgamation. The coefficients of expansion were calculated from these results and found to diminish with increasing concentration. The heat capacities were found t o be distinctly larger than the sum of the heat capacities of the thallium and mercury in the amalgam. This excess is greater in dilute than in concentrated amalgams.The heat of dilution with mercury was determined a t 20° and from the results the values a t 30° and 3 2 5 O were calculated. Although the heat of dilution of thallium amalgam is a very different effect from the transfer of thallium from one amalgam to another it is shown that either of these effects may be calculated from the other. Within the limits of experimental error the heat effects in the cells of which the E.M.F. was measured may be calculated from either the heat of dilution of the amalgams or the heat of solution of thallium in the amalgams or the temperature-coefficient of the E.M.F. each of these three methods giving essentially identical results within the limits of experimental error. The freezing points of amalgams containing from 16 to 45 atomic % of thallium were found to give a curve indicating conclusively the existence of the solid compound Tl,Hg,. The single potential of pure electrolytic thallium was found to be about 2’5 m.v. more negative than that of saturated thallium a t the ordinary temperature. Nitrous-Nitric Complexes of Thallium.L. ROLLA and G. BELLADEN (Gazzetta 1919 49 ii 217-224).-Thallium nitrite W. G . J. F. S.IXORGANIC CHEMISTRY. ii. 35 like barium strontium and calcium nitrites (compare Vogel A. 19d3 ii 391) has a specific electrolytic conductivity below that of the corresponding nitrate and undergoes normal dissociation. The B.M.F. of the cell thallium amalgam 1 -IT/ 10-thallium nitrite 1 normal electrode is 0.667 volt a t 25O the same value being obtained if the nitrite is replaced by the nitrate.Peters found that lead nitrate and nitrite interact in solution. forming well-defined compounds containing both salts. Similarly thallium nitrite and lead nitrate react yielding compounds contain- ing Pb T1 NO NO and OH. With potassium nitrite and thallium nitrate however despite wide variations in the concentra- tions of the reacting solutions no product containing potassium could be obtained ; the nitrate-nitrites formed although they have compositions differing greatly from those of Peters' salts are stable and may be recrystallised unchanged. If the two reacting salts are taken in molecular proportions the resultant product has the percentage composition T1 76.65 NO 20.58 and NO 2.76 whilst in the proportion TlNO and 2KN0 the compound obtained has the formula Tl,N,O the ratio of NO to NO in the complex ion being 2 1.With 3 mols. of potassium nitrite and 1 mol. of thallium nitrate the product has the percentage composition T1 82.78 NO 6.64 NO 5.80 and OH 4.78 and with 4 mols. of the nitrite to 1 mol. of the nitrate the composition is T1 86.22 NO 1.27 NO 4.17. and OH 8.34. T. H. P. Investigations on some Rapid Low Temperature Reactions by means of Heating Curves. J. ARVID HEDVALL and NILS VON ZWEIGBERGK (Zeitsch. anorg. C'hem. 1919 108 119-136).- I n a previous paper (A. 1919 ii 26) it was shown that the decom- position of barium peroxide takes place a t a much lower tempera- ture in presence of all modifications of silica than when heated alone a certain amount of barium silicate being formed a t the same time.The behaviour of a great number of other oxides when heated with barium peroxide has now been studied by examining the heating curves of the mixtures in molecular proportions. Cuprous oxide reacts violently with barium peroxide a t about 1 30° and is completely oxidised to cupric oxide. The latter decomposes barium peroxide catalytically the optimum temperature being about 660O. Magnesium and calcium oxides start the decomposi- tion of the peroxide at 250° and 310° respectively whiIst zinc oxide brings about slow decomposition between 200° and 370° and at the same time forms barium zincate. Purely catalytic adio is shown by cadmium oxide lanthanum oxide and cerium peroxide whilst zirconium oxide and stannous and stannic oxide are without action.Alumina acts catalytically and forms an aluminate. Titanium oxide and barium peroxide in molecular proportions when heated below 300O. evolve oxygen slowly; above 300° a titanate is formed probably BaTiO,. When the proportions 2Ba02 to TiO are used a basic titanate completely soluble in acetic acid is formed. Litharge and barium peroxide between 300° and 400" 2*ii. 36 ABSTRACTS Oh’ CHEMICAL PAPERS. give no oxygen but form a brown product the nature of whicli has not been determined. Above 500° much oxygen is evolved and a product formed probably Ba,PbO which leaves a residue of lead peroxide when treated with nitric acid. Vanadium pent- oxide reacts vigorously with barium peroxide. When equimolecular proportions are used reaction begins a t 215O and is ended at 53OC barium metavanadate Ba(VO,) being formed.With 2Ba0 the metavanadate is first formed but a t 375O a second very vigorous reaction starts and the colour changes from brown to white the product formed being apparently Ba,V,O,. Tantalum pentoxide also reacts vigorously with formation of a tantalate. When arsenic trioxide is heated with barium peroxide (3 mols.) arsenic pentoxide is first formed at 310° t o 410° and above 4 6 5 O evolution of oxygen begins and barium arsenate is formed. Antimony tri- oxide behaves differently as a t 200° oxygen is evolved with almost explosive violence. Bismuth trioxide starts a gradual evolution of oxygen a t about 25OC and higher oxides of bismuth or compounds of theae with barium oxide appear to be formed.Chromium sesquioxide is rapidly oxidised above about 225O without evolution of oxygen barium chromate being formed. The oxides MOO WO U,O and UO all cause evolution of oxygen and form molybdates tungstates and uranates respectively. The lower oxides of manganese are all oxidised barium manganate being formed. Ferric oxide acts catalytically and a t the same time ferrate is formed. Nickel and cobalt oxides both act catalytically and are at the same time changed into higher oxides which how- ever do not agree in their properties with the known peroxides of these metals. E. H. R. Basic Exchange in Permutite. V. ROTHMUXD and G. KORNFELD (Zeitsch. anorg. Chem. 1919 108 215-225).-1n a previous paper (A. 1918 ii 315) basic exchange between univalent metals in permutite was studied. The inquiry has now been extended to bivalent metals with the study of the exchange between copper permutite and the nitrates of magnesium calcium strontium and barium and it has been confirmed that with equivalent ions the reaction is independent of the dilution.The tendency t o permutite formation is least with magnesium and increases steadily from calcium to barium. For the equilibrium between uni- and bi-valent ions the equation takes the form ( c 1 ’ ) 2 / c z l . (cp/c12)fl=K and this formula has been verified for the exchange between silver permutite and barium nitrate and for t h a t between calcium and sodium in sodium and calcium permutites. I n the latter case a gap was found in the series showing that calcium and sodium permutites are not completely miscible. The equilibrium for these cases is not independent of the dilution.A few experiments on the exchange between lanthanum and silver permutites showed that in this case the dilution has a marked influence on the equilibrium. Preparation of Colloidal Mercury by Cathodic Dis- integration. A. GUTBIER and G. L. WEISE (Kollozd Zeztsch. 1919 25 97-130).-Colloidal solutions of mercury may be prepared by E. H. R.INORGAKIC CHEMISTRP. ii. 37 striking an arc between a clean mercury surface and a thin platinum foil catlode under water. The most suitable current to employ for the purpose is 3 4 amperes at either 110 or 220 volts. By this means at. ordinary temperatures the sols are obtained which have a grey colour and change from light grey to bluish- grey and then to grey as the concentration increases.The sols are not very stable; on keeping they coagulate in about twenty-four hours and are coagulated by very small quantities of electrolytes. I n all cases the coagulation is irreversible. Much more stable sols are produced when a protecting colloid is present; thus using 1 10 or 1 50 gum arabic solution in water grey sols are produced which may be preserved for ten to fourteen days. These sols are also very sensitive to electrolytes and are irreversibly coagulated by the addition of alcohol. J. F. S. Scandium. R. J. MEYER and B. SCHWEIG (Zeztsch. anorg. Chem. 1919 108 303-317).-Jk was shown in a previous paper (A. 1914 ii 369) that the atomic weight of scandium given in the Inter- national tables cannot be accepted as a final figure. The impuri- ties likely to be present in scandium preparations separated by the usual methods from the other rare earths are traces of thorium and of the elements of the yttrium earths.It has now been found that complete separation of scandium from these impurities can be effected by fractional crystallisation of scandium formate or of ammonium scandium fluoride (NH,),ScF,. A sample of scandium oxide the spectrum of which showed no trace of yttrium lines and only faint traces of those of thorium and ytterbium was frac- tionated by the formate method and when the most soluble frac- tion was examined spectroscopically the lineis of all these elements showed up very strongly showing that the spectroscopic test for them is not so sensitive as is usually supposed.The least soluble fraction appeared to be pure scandium formate and the atomic weight of the metal determined by the sulphate method was 45.33 to 45.35. Ammonium scandium fluoride was crystallised from hot weakly ammoniacal aqueous solution. The impurities separated first from the hot solution and after these had been filtered off the solution was allowed to cool. After two or three such crystallisa- tions the spectrum of the double salt showed no signs of the presence of foreign elements. Atomic weight determinations on the pure materials thus prepared were made by Honigschmidt by analysis of scandium bromide the mean result of a series of experi- ments pointing to 45.1 as the true atomic weight of scandium (A.1919 ii 285-286). This is one whole unit above the accepted value. The present authors confirm Honigschmidt’s conclusion that an exact determination of the atomic weight cannot be made by the sulphate method on account of the impossibility of preparing a pure scandium sulphate free from both basic and acid salts. E. H. R. The Changes Undergone by certain Alloys of Aluminium. LBON GUILLET (Compt. rerid. 1919 169 1042-1043).-1t has 2*-2ii. 38 ABSTRACTS OF CHEMICAL PAPERS been shown previously (A. 1902 ii 364) that certain alloys 01 aluminium with either iron manganese or nickel rapidly crumble to powder in the air. These experiments have been repeated and this time the alloys of aluminium with iron o r nickel remained stable. The aluminium-manganese alloy containing 86.4% of man- ganeee crumbled very rapidly in the air but more slowly in oxygen nitrogen or hydrogen without gaining in weight.The change is to an allotropic modification. Similarly an alloy of aluminium and antimony fell to powder in moist air but not in dry air but in this case the change was chemical oxidation taking place. W. G. The Ternary System Aluminium-Copper-Zinc with Reference to Zinc in Particular. V. JARE; ( h i . Zeitsch. Metdlog. 10 1-44; from Chenz. Zenty. 1919 iii 512-514). -The literature of the binary systems Al-Zn A1-Cu and Cu-Zn is critically reviewed in addition to that of the ternary system with reference to copper. The author has chiefly investigated the portion of the system Al-Zn-CuAl-CuZn,. This can be resolved into four equilibria triangles to each of which a ternary non- variant pseudo-eutectic point belongs which (except in one doubtful case) lies outside the equilibrium triangle. A t 424O with 68% zinc 12% copper and 20% aluminium reaction is expressed by the scheme aluminium mixed crystals + fused mass A1,Zn3 + CuA1,; at 418O with 72% zinc 11.5% copper 16.5% aluminium the equation is CuA1 + fused mass Al,Zn3 + CuAl ; a t 406O with 79.5% zinc 9% copper and 11.5% aluminium equilibrium occurs as follows Al,Zn,+CuZn f fused mass; a t 386O with 94% zinc 1% copper 5% aluminium the reaction is CuZn,+fused mass S Al,Zn,+Zn mixed crystals; a t 590° with 76% zinc 23% copper 11% aluminium equilibrium occurs thus 6+fused mass CuAl+ CuZn,.Ternary compounds were not observed. The alloys were prepared by melting the requisite amounts of the pure metals in unglazed crucibles in an electric furnace with alloys containing 20 50 and 70% of copper.The temperatures were measured with platinum-platinum rhodium or with silver-nickel thermo-elements (calibrated by the m. p.’a bismuth 269O lead 327O zinc 419O 3b 630‘5O). The changes in the solid alloy resulting from the decomposition of the compound Al,Zn a t 256O were not investigated. The microscopic observations were made with sections etched with aqueous sodium hydroxide solution (2%) or alcoholic picric acid (2%). The mechanical properties of alloys of aluminium copper and zinc rich in the latter have been investigated; t o secure a near approach to the technical alloys commercial zinc containing about 1% of lead was used. The hardness of slowly cooled specimens in the system Zn-A1 increases rapidly with the aluminium content to about 70 a t 10% Al remains constant to about 20% Al and then increases very slowly; it reaches a maximum in the system Zn-Cu at about 5% Cu sinks to a minimum a t 12-14% Cu and subse- quently increases very rapidly.The minimum of the Zn-Cu alloyINORGANIC CHEMISTRY. ii. 39 is also observed in the ternary system Al-Cu-Zn in slowly cooled specimens but is absent from quickly cooled specimens ; the hard- ness increases considerably more uniformly. The tenacity of Cu-Zn alloys shows a maximum a t about 10% Cu whilst that of Zn-A1 alloys increases fairly rapidly with addition of copper to about S-lO% Cu and then sinks. Fractured surfaces of zinc become finer by addition of aluminium without altering the usual structure; addition of copper causes little alteration in the region of the zinc mixed crystals but subsequently the fracture is more finely granular.The compressibility of alloys of zinc 90%. Cu 6% and A1 4% has also been investigated. The tenacity and hardness of brass or ordinary bronze is readily attained in Al-Cu-Zn alloys but the brittleness of the latter make them an imperfect substitute for the former. The technical possibilities of A1-Cu-Zii alloys rich in the latter are discussed. The maximum useful copper content is estimated at about lo% the minimum a t about 4"/. Aluminium should not exceed 5% and should be diminished with increasing amounts of copper. The alloys are not suitable for steam; they oxidise too readily only withstand moderate pressure and are corroded by many salt solutions alkalis and natural waters.They can only be used with caution in making parts subject to considerable mechanical strain. They are frequently useful f o r fine mechanical The Ternary Systems MgO-A1,Oa-SiO and CaO-A120a- MgO. A. MEISSNBR (Zenzem! 8 296-298 308-310; from Chem. Zentr. 1919 iii 511) .-The temperahre-concentration relationships in the first system of the different crystalline phases in equilibrium with the liquid phases have been investigated and the results are expressed in diagrams and by a model. A ternary copzpound 2Mg0,A1203,Si0 unstable a t its m. p. and showing considerable tendency to the formation of mixed crystals has been observed in two forms ; the unstable p-variety crystallises from glasses a t a temperature of about 950° and passes a t a somewhat higher temperature into the stable a-variety.The properties of both forms more particularly of the a-form are similar to th3sn of the mineral cordierite. The system CaO-Al&MgO is QXK- paratively simple since it does not yield a ternary compound which is stable in the presence of the liquid phase. Its investigation therefore is concerned with the equilibrium of the components CaO A1,0 and MgO and of their binary compounds 3CaO,Al,O 5Ca0,3AI20 CaQ,A1,03 3Ca0,5A1,03 MgO,A1,0 in ternary solution. The results are expressed in a series of temperature- concentration diagrams. A new form of aluminium oxide. is designated P-AI,O,. The relationship of each of the forms in the binary system MgO-A1,0 demands the presence of solid solutions the amount of which has been estimated.Manganese-Bismuth Manganese-Zinc and Manganese- Silver Alloys. PAUL SIEBE (Zeitsch. anorg. Chem. 1919 108 161-183).-The condition diagram for manganese-bismuth alloys work such as physical instruments. H. w. H. W.ii. 40 ABSTRACTS OF CREWICAL PAPERS. has been determined by the cooling curve method. The two metals are not completely miscible. When more than 23% of manganese is present two layers are formed t h e upper consisting of practic- ally pure manganese whilst the lower is a 23% solution of man- ganese in bismuth. Five arrest points were found corresponding with five crystalline phases. The eutectic horizontal is at 259O and the other four horizontals corresponding with the arrest points are at 442O 59'i0 1043O and 1252O.The last represents a eutectic containing a t m.ost 0'5% bismuth which lowers the melting point of manganese 13O. From alloys containing up t o 0.5% of manganese pure bismuth first separates; with 0-5 t o 9% of manganese the first compound separates; from 9% t o 11% a second compound and from 11% t o 20% a third. The nature of the compounds has not been determined. Bet%ween 23% and 99.5% of manganese there is a complete gap. The microscopic appearance of the different crystalline phases is described. The hardness of the alloys increases with the manganese content. They are ferromagnetic and this property has been shown to be peculiar t o the first compound crystallising from alloys containing between 0.5% and 9% of manganese. Alloys of zinc and manganese could be prepared containing only up to 50% of manganese.Those containing from 0% t o 11% of manganese show an arrest point at 416O the eutectic point. The eutectic compound contains a very small undetermined quantity of manganese which lowers the melting point of zinc 3O. The mixed crystal constituent of the eutectic contains 11% of man- ganese and a series of mixed crystals are formed containing up to 50% of manganese. The alloys are brittle and increase in hard- ness as the manganese content increases. The behaviour of a series of manganese-silver alloys with a number of chemical reagents has been studied. A sharp distinc- tion was found between those containing 0.22 and 0.24 mol.of manganese and those containinc 0.26 and 0.28 mol. respectively. The latter pair were readily attacked by silver sulphate solution. with deposition of silver; by copper acetate and copper sulphate with deposition of copper ; and by sulphuric and hydrochloric acids with liheration of hydrogen whilst the former pair containing less manganese were unattacked. There was found a similar shai-1) difference when the electric potentials of the two pairs were com- pared. Those alloys containing more than 0.25 mol. of manganese appear t o behave both chemically and electrically practicallv as pure manganese. E H. R. I. BELLUCCI (Gazzetta 1919 49 ii 180-186).-The author has isolated the tervalent manganese fluoro-salt which causes the anomalous results obtained when Lunge's method of estimating nitrous acid by means of per- manganate is applied t o solutions containing fluorine ions in high (,oncentration (compare A 1919 ii 476).This salt KIMnFj,H,O. which belongs to the only known type of fluc-salts of tervaleiit :i:qnganese may be obtained by the action of nitrous acid in Fluoro-salts of Tervalent Manganese.INORGANIC CHEMISTRY. ii. 41 presence of hydroRuoric acid either on potassium permanganate or on a manganous salt the nitrous acid acting in the former case as a reducing agent and in the latter as an oxidising agent. T. H. P. The Atomic Weight of Iron. ALOIS BILECKI (Zeztsch. angig. Chent. 1919 108 318-320).-In a previous paper the atomic weights of silver and oxygen were compared through t h a t of man- ganese (this vol.ii 26). A similar comparison can be made through the atomic weight of iron. Baxter by analysis of ferrous bromide found Fe=55.8378 when Ag= 107.88 o r Fe=55.90 when Ag=108'00. By analysis of ferric oxide Richards and Baxter obtained in two series of experiments 55.90 and 55.883 taking 0 - 1 6 . A careful comparison of the data of the individual ex- periments establishes the fact t.hat the ratio of silver t o oxygen must be 108 16 or 107.88 15.9822 thus confirming the conclusion which was arrived a t from a consideration of the atomic weight of manganese. E. H. R. The Penetration of Iron by Hydrogen. T. S. FULLER (Y'tuu\. &lnter. Electrochem. Soc. 36 16 pp.).-Penetration of iron by molecular hydrogen begins a t 325O and increases rapidly Gith the temperature but nascent or atomic hydrogen penetrates iron at the ordinary temperature as shown by these experiments.An iron tube with 1/16-in. walls connected a t the ton to a U-tube device f o r measuring the volume of gas entering the tube through its walls. was immersed in a 1% solution of sulphuric acid. Hydrogen generated on the outside of the tube passed through the walls the rate varying with the conditions. The rate was greater for a unit immersed without electrical connections than when the unit was used as a cathode but in the latter case the greater the current the greater is the penetration. The rate also increases with temperature. Copper is not penetrated by nascent hydrogen but a coating of tin on the iron increases the rate.Results are given for other conditions and electrolytes. It was proved t h a t there was no peiietratiou by acid but by gas alone. CHEMICAL ABSTRACTS. Tin Hydride. I. FRITZ PANETH arid KARL FijRTH (Bey. 1919 52 [HI 2020-2029).-The authors have applied the method which was successfully used in the study of bismuth hydride (Paneth and Winternitz A. 1919 ii 68) to the problem of the isolation of a hydride of tin. An alloy of tin and magnesium corresponding with the formula Mg,Sn is dissolved in 4A7-hydrochloric or sulphuric acid ; the gas which is evolved is filt,ered through cotton- wool dried by calcium chloride and phosphoric anhydride and led through a heated hard-glass t.ube; a mirror of metallic tin is formed in close proximity to the hot part of the tube which when well developed consists of three zones a whitish-grey blackish-grey to black and finally brown in colour. The reactions of the mirrorii.42 ABSTRACTS OF CHEMICAL PAPERS. are very fully described the most distinctive of them being the insolubility in cold concentrated nitric acid and the formation of purple of Cassius and calomel by gold and mercuric chlorides respectively after preliminary treatment of the ring with dry gaseous hydrogen chloride. Preliminary experiments also show t h a t the gas can be condensed by liquid air and re-evaporated with- out decomposition so t h a t its collection in some quantity appears possible. The yields however are as poor as in the case of bismuth hydride oiily a few thousandths per cent. of the tin of the alloy being converted into the hydride.[With A. M ~ R s C ~ ~ ~ ~ . ] - P r e l i m i n a r y experiment appears t o show that lead hydride can exist in the gaseous state. It is formed from the magnesium-lead alloy in yield which is worse than in the cases of bismuth or tin but better results are obtained by an electrolytic process of reduction. H. W. The Question of the Existence of Zirconium Monoxide. ROBERT SCHITVARZ and HCGO DEISLER (Ber. 1919 52 [n]. 1896-1903).-Winlrler ( A 1890. 1375) Dennis and Spencer ( A 1.896 ii 558) and Wedekind (A. 1905 ii 596) have studied the reduction of zirconium dioxide by magnesium and obtained black powders which recombined with oxygen on heating in the air. the increase in weight approximating to t h a t required by the formula ZrO.The experiments have been repeated under various condi- tions (in a Rose crucible in a combustion tube in an atmosphere of carbon dioxide in porcelain tubes a t 1000O filled with carbon dioxide or hydrogen or evacuated and in a crucible fired by thermite) but i t is found that it is quite accidental t h a t the black powder left after removing the excess of magnesium and its oxide should increase by the theoretical quantity (nearly 155L) on heating in oxygen. I n fact the more quickly the reduction is performed the greater is this subsequent absorption of oxygen rising in one case t o 28%. It appears therefore that the black powder is a mixture of metallic zirconium and its dioxide To test this assumption varioiiq specimens of the powder were heated at about 250° in a stream of chlorine or a t high temperature. in hydrogen chloride gas the sublimate being analpsed.It was expected that the free inetal would give the tetrachloride the diovide remain unattacked and the monoxide. if any produce water in the case of hydrogen chloride. No indication whatever could be obtained of the presence of the monoxide. The sublimate consisted of the tetrachloride. and its weight aqreed exactly with the increase of weight suffered by the powder when heated in oxygen. The dioxide iq not attacked at all. even at 500O. J. C. W. F. P. VENABLE and I. W. SMITHEY ( J . .4mer. Chem. S o r . 1919 41. 1722-1 7 2 7 ) .-Zirconium hydroxide does not dicsolve in iodic acid. and therefore zirconium iodate waq prepared by adding iodic acid solution to a solution of zirconyl chloride.when a white precipitate Zirconyl Compounds with the Oxy-halogen Acids.INORGANIC CHEMISTRY. ii. 43 insoluble in water alcohol and ether was obtained. It was ileconi- posed by hydrochloric acid with evolution of chlorine and a t 125' iodine was evolved. The precipitate was filtered without any wash- ing and other samples were filtered and washed with measured volumes of water with the object of determining the amount of hydrolysis. The unwashed precipitate had the composition ZrO(OH)2,2ZrO(I03) when obtained from concentrated solutions but from dilute solutions the salt is more basic and has the com- position 5Zr0(OH),,8ZrO(I03)~. When the second compound was washed with 6 litres of water a t the ordinary temperature the compound had the composition 3ZrO(OH),,4ZrO(I03),.On wash- ing with 20 litres of boiling water the compound 2ZrO(OH),,ZrO(TO,) was obtained and with 30 litres of boiling water the compound 3ZrO(OH),,ZrO(I0,)2 was produced. Zirconium hydroxide is readily soluble in 30% perchloric acid. When the action was allowed t o take place a t the ordinary temperatures the compound ZrO(C10,)2,HC10 crystallised out in large triclinic crystals but when perchloric acid was heated with an excess of zirconium hydr- oxide the compound Zr0(OH),,9ZrO(C104) was obtained in crystal clusters which were soluble in alcohol ether benzene chloroform or carbon tetrachloride but could not be recrystallised from these solvents. On adding potassium chlorate to a cold con- centrated solution of zircoiiyl perchlorate crystals of basic zirconyl chlorate Zr0(OH),,3ZrO(C103) were obtained.The crystals were extremely deliquescent very soluble in alcohol but insoluble in ether. They were faintly yellow in colour had an odour of chlorine dioxide and oxidised organic matter very readily J. F S. Elimination of Vanadium from the Arsenical Waters of the Bellville District Province of Cbrdoba Argentine. FREDEKICO REICHERT and RAUL WERNICEE (Anal. SOC. Quim. Aiyentina 1919 7 ll0-113).-Solutions of ferric salts and of ferrous sulphate added in small quantit,ies to alkaline solutions of sodium vanadate cause the precipitation of the vanadium as i n - soluble ferric vanadate and also by adsorption on the ferric hydr- oxide formed. It is proposed t o apply the method for the simultaneous removal of arsenic and vanadium from natural waters.w. s. M. [Preparation of Potassium Pyroantimonate for the Esti- mation of Sodium.] J. D. VAN LEEUWEN (Chem. Weekblad 1919 16 1426) .-Potassium pyroantimonate which will remain un- affected for a prolonged period is made as follows 20 grams of potassium antimony1 tartrate are mixed with an equal quantity of potassium nitrate and the mixture is heated to redness in a crucible. When reaction has ceased the lid is placed on the crucible and heating continued for fifteen minutes. After cool- ing 50 C . C . of warm water are added and the mass stirred until it 2" *ii. 44 d\RSTRACTS OF CHEMICAL PAPERS. liecomes powdery. It is then filtered through a porcelain vdciiuiii filter the residue is treated with 100 C.C.of cold water and trans- ferred with the filter paper to a flask containing 500 C.C. of boil- ing water. After boiling for one minute and rapidly cooling some aluminium hydroxide is added the mixture is shaken and finally passed through an ordinary filter paper. W. J. W. Bismuth Thiosulphate Compounds. L. VANINO and F. MUSSGNCG ( A ~ c h . Pharm. 1919 257 264-266).-The authors have prepared various double thiosulphates of bismuth by making use of bismuth-mannit,ol solution. Hauser ( A . 1903 ii 48i) describes an unstable bismuth sodium thiosulphate but a stable compound BiNa,(S,O,) which crystallises in small octahedra is obtainable by the interaction of bismuth-mannitol solution and sodium thiosulphate in presence of manganese chloride. Bism21th ammoti,ium thiosuzphate Bi(NH,),(S20,),,2H,O forms a yellow precipit,ate which soon changes colour and 011 solution in water undeqoes decomposition.Rifirn~ith .strot~.tiirnz thiosii7pIiate prepared from bismuth-mannitol solution and strontium thio- sulphate forms a yellow indistinctly crystalline mass and under- goes hydrolysis when dissolved in water. The bismuth-silver com- pound similarly obtained forms a yellow precipitate becoming black in a few seconds; thO bismuth-copper compound is pre- cipit.ated only on addition of alcohol. Unsuccessful attempts were made to prepare bismuth dithionate and trit.hionate. On addition of sodium trithionate (compare Willstatter A. 1903 ii 543) to bismuth-mannit.01 solution. the liquid soon blackens; as this behaviour is not shown by sodium dithionate the presence of bivalent sulphur in trithionic acid is proved.T. H. P. s r 3 p (S203)312! Platotriammine Sulphite. D. STRdarHoLtr (Zeitsch. cmorq. Chem. 1919 108 211-214).-When the ammonium salt. of tri- chloroplatosulphonic acid is warmed in aqueous solution with excess of ammonia platotriammine sulphite Pt(NH,),S03 is formed as a sparingly soluble white microcrystalline powder. It. seems t o he identical with the substance which was described by Birnbaum (dnnalen 1869 76 142) as platotetrammine sulphit'e. When its hydrochloric acid solution is oxidised with chromic acid the diammine Pt(NH,),Cl is formed. Solubility determinatioiis showed t h a t only t.he tmns-isomeride was formed. This conclusion was confirmed by the preparation of the osalate which is quite distinct from that given by the' cis-compound .E. E. R . Platinitetrammine Disulphite. D. STR~MHOLM (Zeitsch. anorg. Ch,em. 1919 108 184-190).-To determine d.eSnitely whether the compound prepared by Cleve by the action of sulphurous acid on Gros's nitrate PtC1,(NH3)4(N03) contains bi- or quadri-valent platinum a study of its formation reduction,MINERALOGICAL CHEMISTRY. ii. -15 and oxidation lias lieen made with the result that the compound has been proved to have the composition Pt(NH,),(SO,),,SH,O. The yield of the disulphite obtained from the nitrate is only about 6676 of the theoretical and a certain amount of sulphuric acid is formed during the reaction but not so much as would be required t o be formed if the platinum were reduced from the quadrivalent to the bivalent condition. When the compound is oxidised by means of chromic acid the oxygen used is all accounted for by the oxidation of the sulphurous acid t o sulphuric acid t h a t is t o say there is no oxidation of the platinum. The product of the chromic acid oxidation is a chromi-chromute of the formula By prolonged heating with dilute sulphuric acid this compound is transformed into the salt [(OH)(SO,)Pt(NH,),]Cr,0 previously prepared by Cleve. The same two chromates were prepared from Rajevski’s nitrate [(OH)ClPt(NH,),](NO,),. When the platinitetrammine disulphite is boiled with water or heated with acids platinotetrammine sulphate is formed the quadri- valent platinum being reduced by half the sulphurous acid which becomes oxidised t o sulphuric acid whilst the other half of the sulphurous acid escapes. The same reaction takes place incom- pletely when the salt itself is heated. [(OH)~S0,P~(NH,)s11pCr,07,Cr0,. E. H. R.

ISSN:0368-1769    

DOI:10.1039/CA9201805028

出版商:RSC    

年代:1920

数据来源: RSC

摘要:

MINERALOGICAL CHEMISTRY. Miner alo gi c a1 Chemistry. ii. -15 The Genesis of Petroleum as Revealed by its Nitrogen Constituents. CHARLES F. MABERY (J. Awzer. Chent. SOC. 1919 41 1690-1697).-1t has already been shown that the heavier varieties of petroleum in the California Texas Ohio Canada Russian and similar fields are complex mixtures of the denser hydrocarbons with oxygen sulphur and nitrogen derivatives. They all differ widely in composition from the lighter varieties in the eastern territory. An examination of twenty-one specimens of the latter however discloses in every case the presence of nitrogen in amount varying from 0.01 t o 0.4874 so that the conclusion is justified that nitrogen is contained in the petroleum of all the principal oil fields in forms of combination which could have had their origin only in the remains of vegetable or animal bodies.Presumptive evidence has been shown that the associated hydre carbons in petroleum had the same origin. Nitrogen is estimated by Kjeldahl's method on the one hand and by a process which is a combination of the Dumas procedure for nitrogen and the oxygen combustion for carbon on the other. For details of the latter and of the special precautions required in the estimation of such minute proportions of nitrogen in oils the 2**-2ii. 46 ABSTRACTS OF CHEMICAL PAPERS. original paper must be consulted. two methods show very fair agreement. Thc resuits ok)iaiiierl by the H. W. Probable Identity of Peganite with Variscite. LORENZO MOSCHETTI (Atti R . Accad. Sci. T o T ~ ~ o 1917-1918 53 652-656).-The author has analysed and examined physically Breithaupt's peganite ( J . Chem. Physzk 1830 6Q 308) his results indicating the identity of thia mineral with variscite. The composition given by Hermann ( J . p. Chem. 1844 33 287) for peganite is erroneous. T. H. P. Identity of Spangite with Phillipsite. F. ZAMBONXI (Attz €2. A ccad. Sci. Torino 1917-1918 53 47-54).-The spangite described by Mantovani (private communication 1872) is found t o be devoid of magnesium and its crystallographic characters show t h a t it is identical with the phillipsite of the leucitites found in the neighbourhood of Rome. The Minerals of the Valley of Gava in the Voltri Group ; a New Varietyof Talc. EMILIO REPOSSI (Attz SOC. Itnl. Sca. Nut. 1918 57 131-155).-The geology of the region is outlined and a number of minerals described.Crystallography or other features are given of garnet vesuvianite diopside hornblende chlorite titanite apatite pyrite magnetite ilmenite and calcite. Many of these are coated with a mineral which seems to he a new variety of talc and is named gauite after the locality. I t s properties are colour milk-white yellow or green sometimes the calour of nickel salts; lustre in mass velvety on surfaces of individual blades pearly ; structure thin crusts with mammillary surface made up of bunches of flakes. Microscopic study shows aggregate polarisa- tion with the optical properties elongation + ; extinction. parallel; interference colours brilliant; n 1.544 and 1.582 by immersion method about double refraction thus 0.038 ; in all these properties it is similar to talc.It is infusible hefore the blowpipe responds to tests for magnesium and silica and is somewhat readily soluble in hydrochloric acid. T. H. P. Analysis gave Total. SiO,. MgO. FeA. at 110'. above 110' 69.20 28'57 3.23 1.45 6.61 99.06 HgO H,O The water is expelled in two definite stages in the amounts stated. Disregarding the water helow l l O o the revised percentages corre- spond with the formula H,(Mg,Fe),Si,O,,. Gavite differs from talc in the high content of water and i n its solubility in acid. CHEMICAL ABSTRACTS. The Oxidation of Lava by Steam. J. B. FERGUSON (J. Wmhinqtolz Acad. Sci. 1919 9 539-546) .-It is generally sup- posed t h a t water vapour in volcanic gases would have an oxidising action on any ferrous iron present in the lava.Fresh Kilauean lava has been shown t o contain 9.28% ferroiis oxide and 1.92"6 ferrit,ANALYTICAL CHEMISTRY. ii. 47 oxide and this fact might be used as an argument against the presence of a preponde.rance of water vapour in the gases. Very little is known however of the action of steam on silicate minerals containing ferrous iron and a number of experiments are here recorded in which ground Kilauean lava was exposed to the action of water vapour in an atmosphere of nitrogen a t 1000°. As a result of the heating there was found J slight decrease in the ferrous iron content of the rock but this occurred both in presence and absence of steam which behaved as an inert gas. The experi- ments leave no doubt that a considerable amount of ferrous iron when in silicate combinations can exist in the presence of water vapour a t high temperatures.When a sample of the lava was heated strongly in air for two hours the ferrous iron content fell to 1.94% but on again heating in a partial vacuum f o r four hours at l l O O o it rose again t o 3.9%. The bearing of these experiments on the interpretation of results obtained by pumping gases from rocks at high temperatures is eniphasised. ARTHUR M. MILLER (Science 1919 49 541-542).-This meteorite was seen at> midday on April 9th. 1919 passing over north-eastern Tennessee in a course N. 30 W. its progress being noted and in some instances timed by telegraph and telephone operators. It reached the earth in south- eastern Kentucky striking with earthquake violence. A t the time of writing seven pieces ranging from 360 to 2378 grams have been found and their covering of glaze indicates that the splitting off from the main mass occurred at a considerable distance from the ground. F i f t + ~ v o pieces. weighing from less than 30 grams UP to 1800 grams. have been found that are parts of a mass weighing originally about 14 kilos A chemical examination by ALFRED PETER shows the mineral to be mainly enstatite through which is disseminated particle. of nickel-iron and iron sulphides. E. H. R. Cumberland Falls Meteorite. D 3.18. CHEWCAL ABSTRACTS.

ISSN:0368-1769    

DOI:10.1039/CA9201805045

出版商:RSC    

年代:1920

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ANALYTICAL CHEMISTRY. Analytical Chemistry. ii. 47 The Process of Preparation of Charcoal Sticks for Reduction. NESTOR C. ALEXANDRESCU (BUZZ. SOC. chim. Romdnia 1919 1 11-12).-The following process for the preparation of charcoal sticks for the reduction test in qualitative analysis is advocated. Thin wood chips such as are used in match making are boiled for ~ W Q minutes in a 2.5% solution of ammonium phos- phate and then dried a t a temperature not exceeding 60°. When it is required to carry out thr test half the stick is burnt and then the test is carried out in the usual manner on the substance previously mixed with sodium carbonate. W. G.ii. 48 ABSTRACTS OF CHEMICAL PAPERS. Titrations with Surface-active Substances as Indicators. Estimations of Acidity with the Homologues of the Fatty Acids Series.WILHELM WINDISCH and WALTHER DIETRICH (Biochem. Zeitsch. 1919 97 135-156).-Adopting Traube and Somogyi’s method (A.. 1915 ii 101) of estimating the reaction by means of the alteration in the surface tension brought about by the displacement of the acid or the base of the indicator by the acid o r base of the medium the authors tried the homologues of the salts of the fatty acids series up t o undecylic acid as indicators. The acids with C,-C have been found to be as sensitive as litmus and neutral-red. Free acids can be estimated in the Dresence of a primary phosphate by using the above acids as indicators. s. s. z. A Considerable Source of Error in Titrations in the Presence of Phenolphtbalein. HAEUSSERXANN (Sfiddentech.Apoth. Zeit. 1919 59. 361-362; froin Chem. Zenfr. 1919 iv 396).-The author directs attention t o the errors caused by the presence of free carbon dioxide in distilled water which occur in titrations in which phenolphthalein is used as indicator H. W. Preparation of Phenolphthalein Solution and Paper without the Use of Alcohol. H. CLAASSEN (Zentr. Zuckerilzd. 26 209 ; Arch. Suikerind. 1919 26 1588-1590).-When alcohol is unavailable an indicator solution may be prepared by dissolving 1 gram of phenolpht3halein in 12.5 C.C. of N-sodium hydroxide and diluting to 500 c:c. with water. The alkali content of the solution is so small t h a t it can be disregarded in factory work. Where greater accuracy is required the result can be corrected for the alkalinity of the indicator.Test paper can be prepared by immersing paper first in a solution made by diluting 200 C.C. of the above indicator solution to 1 litre drying immersing i t in a solution of sulphuric acid of the proper strength to give the desired acidity and drying again. The results obtained with the paper should be verified from time t o time by direct titration. CHEMICAL ABSTRACTS. Estimation of Bromine in Mineral Waters and Brines. W. F. BAUGHMAN and W. W. SKINNER ( J . Znd. Eny. Chem. 1919 11 954-959).-Chromic acid liberates bromine from bromides quantitatively a t the ordinary temperature and the bromine may be removed by aspiration. Chlorides under the same conditions yield only a trace of chlorine which probably forms chromyl chloride and remains in solution. When a mixture of chlorides and bromides is treated with the reagent some chlorobromide is formed and is removed together with the bromine on aspiration.I n the method of analysis described the residue from the mineral water is oxidised with chromic acid. with the addition of hydrogen peroxide and the liberated heloqens absorbed in a solution of socliLim sulphite and carbonate. This is evaporated and the residueANALYTICAL CHEMISTRY. ii. 49 agaiii oxidised with chromic acid and a current of air aspirated through the apparatus the absorption vessels of which contain potassium iodide solutioii In this second aspiration the quantity of chlorine present is so small t h a t only pure bromine is evolved and its amount is found by titration of the liberated iodine. [See also J .Poc. C'heni. Ind.. 1920 1 9 ~ 1 Test Paper for the Detection of Iodine. ANONYNOUS (J. Phnrm. Brlg. 1919 from ;Inn. Chini. niinl. 1919 [ii] 1 357). -One gram of starch is mixed with 10 C.C. of water 40 c c . of 1)oiling water are added the mixture is boiled f o r two minutes and 0.6 gram of sodium nitrite is then added. The paste obtained is painted on strips of paper by means of a brush. and the s t r i p are dried. To make the test a few drops of the solution under examination are poured on the paper followed by one drop of dilute sulphuric acid. A blue coIoration is obtained if the solution C. A . M. contains iodide. The test paper keeps well. m. P. s. The Spectrocomparator an Apparatus for the Esti- mation of the Percentage Saturation of Blood with Oxygen or Carbon Monoxide.AUGUST XROGH (J. Physiol. 1919 52 281-287; from Ch~n2. Zentr. 1919 iv 210-211).-A modification of Hartridge's method (A. 1912 ii 488) is proposed which gives satisfactory results and only requires small amounts of blood. The apparatus is fully described and figured in thc original which must be consulted for details. H. W. Method for bringing Elementary Sulphur into Solution for Analysis. A. P. BJERREGAARD (J. Id. Eng. Chrm 1919 11 ]OX).-The finely divided sulphur is dicsolved in a small quantity of dry bromine nitric acid is added and the mixture heated The oxidation requires a few minutes only after the excess of bromine has been expelled the mixture is diluted wlth water. boiled with the addition of hydrochloric acid t o expel nitric acid and the sulphuric acid IC then precipitated in the usual way as barium sulphate.w. P. s. Non-protein Sulphur of the Blood. M. KAHN (Proc. SOC. Eap. Biol. Med. 1919 16 139; from Physiol. A h s t r . 1919 4 374). -A method of fractionating and estimating the non-protein sulphur of the blood is described. The Titration of Sodium Thiosulphate Solutions. I. M . KOLTHOFF (Phnrm. Tl'eeX*hlad 1919 56 644-637) -The prepara- tion teqting and application of various substances for the standard- isation of thiosulphate solutions are described in detail and their relative merits for the purpose discussed. The purest forms of potassium dichroniate obtainable commercially contain free chromic acid or potassinin chromate. A method for the detection and esti- mation of these is given which depends on the location of a discon- tinuity in the conductivity curve on the addition of alkali or acid J. C.TI.ii. 50 ABSTRACTS OF CHEMICAL PAPERS. If chromic acid is present the addition of standard alkali causes no increase in the conductivity of a dichromate solution until the free acid is neutralised. Similarly no increase in conductivity is observed on the addition of acid to a solution containing chromate until all the latter has been converted into dichromate. For analy- tical purposes it is recommended to melt the pure dichromate in an electric furnwe before use. The other substances examined are iodine oxalic acid cyanagen iodide potassium iodate and potassiuni brcmate. All these are easily purified. and give results in the titra tion of thiosulphate with an error of less than 0.1%. The greatest emor 0'07"/ waa observed in titrating with dichromate.W. S. M. Influence of the Position of Substituente on the Behaviour of Aromatic Nitro-compounds in the Kjeldahl Estimation of Nitrogen. B. M. MARGOSCHES and ERWIN VOCEL (Bcr. 1919 52 [R] 1992-1998).-The behaviour of the isomeric nitropheriols nitrobenzoic acids and nitrobenzaldehydes when treated with sul- phuric acid and potassium sulphate has been investigated ; it is found that the nitrogen content of the ortho-derivatives can be cor- rectly estimated i n this manner but t h a t the results for the meta- and para-derivatives are much too low. The favourable action of the hydroxy- or alkyloxy-group in the ortho-position t o the nitro-group is further shown by the fact t h a t the process gives exact results with 2-nitroresorcinol 3-nitro-p-cresol and o-nitrophenetole but low results with p-nitrophenetole.A further series of experiments shows t h a t the presence of o-nitrophenol or of o-nitrobenzoic acid has a favourable influence on the behaviour of the corresponding meta- and para-derivatives and t h a t this action cannot be ascribed solely to their content of phenol or benzoic acid. The possibility t h a t condsnsation products of the o-nitro-compounds may be the active agents has led t o an investigation of the behaviour of phthalic acid phthalic anhydride and phenolphthalein under like conditions biit the expected favourable action was not observed. The use of sali- cylic acid appears particularly advantageous in the case of meta compounds.It is somewhat remarkable t h a t the three isomeric iiitrocinnaniic acids yield accurate results. A further series of determinations is recorded with 2 4-dinitro- phenol 2 4-dinitro-a-naphthol 2 4-dinitrobenzoic acid 2 4-dinitro- toluene 3 5-dinitrobenzoic acid 2 6-dinitrotoluene and 2 4 G-tri- nitrophenol; the results are considerably too low in every case although coilcordant among themselves. The facts however that tht 2 4-dinitro-compounds give higher values than the correspond- ing 3 ' 5 - or 2 ' 6-dinitro-derivatives and t h a t 2 4-dinitrophenol gives results almost identical with those obtained with 2 4-dinitrotoluene arc in accordauce with the observations made with the mononitro- compounds. H.W. Grete's Volumetric Method (for Estimating Phosphoric Acid). R. W. TUINZING (Imzdir. VeCielauchs.-stat. 1919 94 191-195. Compare A 1916 ii. 490).-This method was foundANALYTICAL CfIEXISTRY. ii. 51 to be trustworthy. Directions are given for the preparation of the ammonium molybdate-gelatin solution used and for the recovery of ammonium molybdate from t,he residual solutions. W. P. 5. Behaviour of certain Organic Arsenic Compounds in Marsh’s Test. DOWENICO GANASSINI (Boll. Chint Farm. 1919 58 385-390).-The addition of platinum chloride to promote the evolution of hydrogen is inadvisable even in the case of mineral arsenic since it may fix part of the arsenic as platinum arsenide. I n the case of cacodylic acid platinum chloride in large excess com- bines to form a double compound cacodylplatinochloride which may remain undecomposed. An analogous compound is formed between platinum chloride and methylarsinic acid. Cacodylic acid in Marsh’s test produces an orange-yellow deposit in addition t o the ordinary black deposit.This probably consists of erythrarsine. By heating the hydrogen flask to about 335O i n a bath of melted lead only the orange-yellow deposit is obtained. Methylarsinic acid and neosalvarsan under the same conditions also yield yellow deposits but these may be distinguished from the cacodylic acid deposit by the fact that during the formation of the former the gas does not form dense white fumes. The gas from the methylarsinic acid test gives a yellow precipitate with Bettendorf’s reagent (stan- nous chloride solution saturated with hydrogen chloride) whilst the lemon-yellow ring from neosalvarsan is only formed at a high tem- perature does not change to black and is readily soluble in ammonia solution.Atoxyl and salvarsan yield only the ordinary black rings in the test. [See also J. Soc. C h m . Z n d . 1920 4 2 ~ . ] C. A. 31. Separations in the Arsenic Group. WILIIELX S m E c K m and ADOLF RIEDEMBNN (Rep. 1919 52 [U] 1935-1947).-The authors recommend the following modification of the distillation method f o r the estimation of arsenic. The arsenic solution is placed in a flask provided with a dropping funnel and connected through ail efficient worm condenser with a vessel containing water; the flask is half filled with concentrated hydrochloric acid potassium bromide (1.5 grams) and a few pieces of porous earthenware are added.The contents of the flask are heated to gentle boiling and thionyl chloride (10 c.c.) is gradually run in a t such a rate that the time of addition is half an hour. The distillate is diluted with water to 700-800 c.c. boiled under reflux in a brisk current of carbon dioxide until sulphur dioxide is completely expelled and the sulphur has collected (this should be the case in half an hour a t the most) and filtered. Arsenic is estimated in the filtrate as ths trisiilphide. Phosphorus trichloride (25 c.c.) may replace the thionyl chloride in which case the subsequent boiling of the distil- late is unnecessary; on the other hand the presence of phosphorous acid i n the residue often causes complications in subsequent estima- tions.The inethocl gives accurate results and can be applied t o the separation of arsenic from antimony tin copper lead mercury,ii. 52 ABSTRACTS OF C'HENICAL PAPERS. and iron aud for the estimation of arsenic and iron in arsenide of iron. The separation of antimony from tin can be effected by taking advantage of the fact that antimony chloride is volatile a t 155-165O from solutions in which the tin can be rendered non- volatile by the presence of phosphoric acid; the tin can be volati- lised subsequently a t a somewhat higher temperature by taking advantage of the fact that the addition of hydrobromic acid destroys the restraining action of the phosphoric acid. The authors have attempted to shorten the time required for this separation by utilis- ing the catalpsing action of hydrobroniic acid from the commence- ment but the results are unsatisfactory since tin distils over with the antimony the catalpsing influence of hydrogen bromide out- balancing the restraining effect of phosphoric acid.On the other hand the use of hydrobromic acid is very advantageous in the separation of antimony or tin alone from other elements and does not require the absence of nitric acid. Thus i n the separation of antimony aud copper the hydrochloric acid solution of the metals is added to concentrated sulphuric acid (6 c.c.) and phosphoric acid (D 1.78. 7 c.c.) cmtained in a distillation flask connected with a receiver containing hydrochloric acid. The contents of the flask are heated a t l G O o and a mixture of concentrated hydrochloric acid (10 volumes) and hydrobroniic acid (I3 1.78 1 volume) is added a t such a rate that the temperature remains constant.The antimony is completely removed in thirty minutes. The separation of antimony from lead is accomplished similarly. Tin is quantitatively separated from copper and lead in a n analo- gous manner; the solution of the metals in concentrated hydro- chloric acid is treated with sulphuric acid (12 c.c.) and distilled a t 1 GOO with the regulated addition of the hydrochloric-hydrobroniic acid mixture (20 c.c.). The process is complete in half an hour; the tin is precipitated from the distillate as the sulphide and weighed as the oxide. The method call be applied to the estimation of tin in brass. The separation of antimony and tin from mercury cannot be effected in this manner since the latter is also partly volatilised. A novel type of filter tube is described which is constructed by drawing out the end of a piece of wide glass tubing so as t o form a stem; a filter disc covered v i t h asbestos rests on the shoulder of the wider tube which is further provided with a ground-in cap in which a capillary opening is made.Early Developments in Organic Macro- and Micro-analysis. J. V. DUBSK~ (Chem. Tl'eeX blad 1919 16 1482-1493).-The author gives a retrospect of the work of various experimenters in connexion with the analysis of organic substances and indicates the lines along which research progressed. E. OTT (./. Grcsbelricclit 1919 62 89-90; from C'hriii. Z e n f ? 1919 iv 171-172).-Uncertaiii'Lies in fractionaI combustion with copper H.W. W. J. W. Gas Analytical Combustion with Copper OxideANALYTICAL CHEMISTRY. ii. 53 oxide arise in consequence of the dissociation CuO = Cu + 0 which can be eliminated by subsequent repeated passage of the nitrogen over the material in the quartz tube which is maintained a t a low red heat. Preparation of chemically pure nitrogen by means of phosphorus and heated copper oxide is liable to error and recourse should be had to the pyrogallol method. Copper oxide does not appear to be suitable f o r gas analyses in which the carbon dioxide formed by combustion is measured. Estimation of Carbon Monoxide in Blood. D. I). VAN SLPKE and H. A. SALVESEN (Proc. Soc. Exp. Biol. X e d . 1919 16 140; from Physiol.d ? ) s t v . 1919 4 374).-The blood is treated as in the estimation of oxygen by Van Slyke's method. A mixture of carbon monoxide and oxygen with a slight amount of nitrogen is obtained. The oxygen is absorbed by alkaline pyrogallol solution. The residual gag after a correction has been made for nitrogen is carbon monoxide. J. C. D. A Micro-method for the Estimation of Calcium in Blood- serum and other Organic Substances. I). J . DE WAARD (Biochem. Zeitsch. 1919 97 176-186).-The substances are eva- porated and incinerated and the salts of the ash extracted with dilute hydrochloric acid. The calcium is precipitated from the solu- tion as the oxalate which is centrifuged washed dissolved in dilute acid and titrated with potassium permanganate.0.1 Mg. of calcium can be estimated by this method with an error of 4%. A Direct Micro-estimation of Calcium in the Serum. D. J. DE WAARD (Biochem. Zeitsch. 1919 97 lf36-189).-hll the calcium can be precipitated directly from the serum by means of ammonium oxalate and be estimated by the method described in the preceding abstract. The difference between an estimation carried out on tbe incinerated serum and on the original serum was only Ferrous Sulphide as an Indicator in Acidimetry and a New Volumetric Method for the Estimation of Zinc. J. HOUBEN (Ber. 1919 52 [B] 1613-1621).-Since the produc- tion of ferrous sulphide is prevented by the slightest traces of acids it is possible to titrate an acid by adding a crystal of pure ferrous ammonium sulphate passing in well-washed hydrogen sulphide (not enough to saturate the solution) and running in alkali until the black colour of ferrous sulphide is permanent. Experiments with hydrochloric and sulphuric acids on the one hand and alkali hydr- oxides and carbonates or borax on the other show that the end-point is quite as definite as it is in the case of methyl-orange or phenol- phthalein.The only indistinct end-point is found when titrating sulphuric acid with borax but here the difficulty may be overcome by running in more acid until the black colour just disappears again. The method is obviously useful ill the case of colourecl liquids or when working in a bad light. H. W. S . S. Z. 0.001 nig. of calcium per C.C. s. s. z.ii. 54 ABSTRACTS OF CHEMICAL PAPERS. I n the case of zinc salts hydrogen sulphide completely precipitates zinc as sulphide from the sulphate if the solution is less than 0.2AT and from the chloride if the concentration is below 0'067N.A titration of the free acid produced would therefore be a means of estimating ziiic in its neutral salts and here the above use of a ferrous salt proves its worth. The solution is saturated with hydro- gen sulphide some ferrous ammonium sulphate is added and alkali is run in preferably borax solution until the white turbidity becomes brown. A '' back titration '' with an acid is not possible in this case however without first filtering the zinc sulphide as a double zinc-ferrous sulphide is formed which is not quickly broken up. Examples of the application of the method to metallic zinc zinc salts zinc ash and blende show t h a t the results approach those obtained by gravimetric analysis very closely in fact much more so than those given by any other volumetric method.Blende is examined as follows. About 5 grams of the mineral are digested with 40 C.C. of concentrated hydrochloric acid and 40 C.C. of water the solution filtered and saturated with hydrogen sulphide filtered again and diluted to 1000 C.C. with dilute hydrochloric acid. Por- tions of 50 C.C. are now neutralised with sodium carbonate using methyl-orange treated with hydrogen sulphide f o r half an hour mixed with ferrous ammonium sulphate and titrated with borax or sodium carbonate. The alkalimetric titration of ferric salts may be carried out by employing the same principles.Electrometric Analysis with Potassium Ferrocyanide. ERICH MULLER (Zeztsch. nngezu. Ckem. 1919 32 351-352).- Electrometric titration of lead and zinc salts with potassium ferro- cyanide solution is trustworthy but the method fails in the case of other metals owing to the fact that the precipitates produced do w. P. s. Colorimetric Estimation of Lead Dioxide in Litharge. WALLER V. MORGAN (J. Incl. ICny. C'hem. 1919 11 1055).-The method depends on the fact that lead dioxide oxidises aniline to aniline-purple and t h a t the coloration obtained is proportional t o the amount of the dioxide present. Five grams of the litharge con- taining lead dioxide are boiled for one minute with 2 grams of aniline hydrochloride dissolved in 10 C.C. of water and 5 C.C. of concentrated hydrochloric acid ; the mixture is then filtered and the coloration exhibited by the filtrate compared with those given under the same conditions by litharge containing known amounts of lead Complex Internal Salts in Quantitative Analysis.I. I. BELLUCCT and A . CHIUC~NI (G'azirttn 1919 49 ii 187-216).- The authors summarise and criticise published work on the itpplica- ticjns of a-nitroso-P-naphthol and ' I ciipferron ' to the separation and estimation of metals. Of course cobalt and nickel salts must be absent. J. C. W. not have definite compositions. peroxide. w. P. s.ANALYTICAL CHEMISTRY. ii. 55 For the separation of copper neither of these reagents offeis appreciable advantages over ordinary analytical methods except perhaps for the separation of copper from arsenic and more parti- cularly from antimony.For the separation of iron cupferron is t o be preferred t o u-nitroso-P-naphthol chiefly because the ferric precipitate obtained with the former withstands a greater degree of free mineral acidity and is therefore more easily freed from extraneous metals and also because the precipitate is less volumin- ous. a-Nitroso-P-naphthol serves principally as a reagent for cobalt and also as a reagent for palladium whilst cupferron acts as a reagent for titanium zirconium and vanadium as well as for iron. The two compounds assume indeed the character of general reagents for groups of elements which contain however elements quite different from those usually classed together. T. H. P. Detection of Cerium.FR. FEIGL ( d s t e ~ r . Chem'Zezt. [iii 22 124-126; from Chem. Zemtr. 1919 iv 592).-Lecoq's reaction is much more distinctly obtained after the addition of a small quan- tity of an aluminium salt but is not applicable in the presence of iron. A vivid blue coloration is obtained when cerium dioxide is moistened with a solution of benzidine in acetic acid ; other cerous and ceric compounds with the exception of cerous fluoride cerous carbonate and double sulphates of cerium behave similarly. The reaction is most sensitive when the solution under investigation is made just alkaline with sodium or potassium hydroxide heated to boiling filtered and the filter paper treated with a drop of benzidine solution; 0.02 mg. of cerium per litre can be thus detected. The other metals which belong to the ammonium sulphide group of the rare earths with the exception of thallium do not show the reac tion The absence of other oxidisiiig agents and of manganese cobalt thallium and chromate is essential since the reaction depends on oxidation.Faintly acid solutions of iron also give the reaction ; after previous addition of sodium or potassium hydroxide a coloration is not observed. I n the presence of iron it is advisable to precipitate cerium as the fluoride and to convert the latter by alkali hydroxide into the hydroxide since precipitated ferric hydr- oxide carries down notable amounts of cerium which are thus removed from the sphere of action. H. W. Soil Analysis. F. 11 uxmn (Laitdzc. Versuclis.-stut. 1919 94 181-1 €39).--For the estimation of iron aluminium calcium mag- nesium pot3assium and phosphoric acid in a soil i t is recommended that 300 grams of the sample be mixed with 900 C.C.of concentrated hydrochloric acid and shaken occasionally during forty-eight hours ; the solution is then decanted filtered and 300 C.C. of the filtrate are eva.porated with the addition of ammonium chloride. The residue obtained is treated with nitric and hydrochloric acids again eva- porated this operation is repeated and the final solution in hydro- chloric acid is used after separation of the silica for the estimation of the above-mentioned constituents. w. P. s.ii. 56 ABSTRACTS OF CHEMICAL PAPERS. Application of Hsematoxylin to the Detection of Iron in Tissues. ,I. MAWAS (Compt. rend. SOC. Bzol. 1919 82 155-158; from L'krm.Z e n t y . 1919 iv 245).-The author considers t h a t the reaction of hematoxylin with ferrous ions is to be ascribed t o salt formation and not as Macallum assumed to oxidation. The latter's statement t h a t the reaction only occurs with inorganic iron is incorrect since iron compounds of the albumins which are not acted on by hydrogen sulphide or ammonium sulphide but are affected by potassium ferro- or ferri-cyanide also show this change. The formation of Prussian-blue is a more delicate test for the pres- ence of iron in tissues; nevertheless the author has obtained useful results with hematoxylin particularly i n certain cases of disease of the eye. The affinity of the haematoxyliii f o r the chromatin of the n~icleus whereby a similar coloration is developed is disadvan- tageoiis.H. w. Brazilin and its Iron Lakes. J. MAWAS (C'ompt. rend. SOC. JIloZ. 1919 82 158-159; from C'hem. Zentr. 1919 iv 245).- Rrazilin is a more sensitive and more rapid reagent than hnniat- osylin (preceding abstract) ; its aqueous solution I'ale red with an orange fluorescence gives dark brown insoluble lakes with ferrous salts. I n aqueous or alcoholic solution it colours tissue containing iron dark brown within a few minutes whilst the nucleus becomes reddish-violet. Differentiation which may be necessary owing to over-colouring is effected with alcohol and chloroform or prefer- ably with alcohol containing 1% of hydrogen chloride. The nucleus becomes practically decolorised whilst the iron pigment is un- affected ; the former again beconies reddish-violet when washed with dilute aqueous alkali.H. W. Iodometric Estimation of Iron. I. M. KOLTSIOFF (Pharm. IVeelcblad 1919 56 1565-1568).-The estimation of ferrous iron by means of iodine with addition of a pyrophosphate gives results which are about 37k too low owing to oxidation of the iodine by dissolved oxygen in the solutions. If sulphuric acid and sodium hydrogen carbonate are added to eliminate the oxygen the error is reduced t o 0.8-1:L. A more suitable method which gives accurate results is the following 25 C.C. of 0.liV-potassium bromate and 10 c c . of 25% phosphoric acid are added to 10 C.C. of O.lll;-ferrous solution to which a few drops of acid have been added. After remaining for five minutes in a stoppered flask 5 C.C.of potassium iodide and 2 drops of molybdate solution are added the iodine being titrated after five minutes with thiosulphate. The purp0.e of the phosphoric acid is to combine with the ferric ions and prevent them interacting with the potassium iodide and the molybdate is added to accelerate the reaction of the bromate and iodide. w 3 w. Volumetric Estimation of Iron. J. HOUBEN (Ber. 1919 Compare this vol. ii 53).-The process 52 [R] 2072-2076.ANALYTICAL CHEMISTRY. ii. 57 perinils the estimation of ferrous and fewic iron and free mineral acid in a solution. A portion of the solution is completely reduced by hydrogen SUI- phide and titrated with -V-potassium or sodium hydroxide solution until the dark coloration due to the incipient precipitation of ferrous sulphide is observed which does not disappear after vigor- ous shaking; the free acid plus one-third of the acid originally com- bined with the ferric salt is thereby estimated A second portion of the solution is reduced with sulphur dioxide (air being completely escluded) most of the excess of the latter is removed by boiling and the cooled solution is titrated with S-alkali as before after being treated with hydrogen sulphide which completes the removal of sulphur dioxide.The free acid plus two-thirds of the acid origiii- ally united to the ferric iron is thus estimated. The difference between the two titrations multiplied by three gives the number of C.C. of .T-ferric chloride solution originally present. If this number is subtracted from the smaller of the two burette readings the dif- ference is the number of C.C.of S-acid which were uncombined iu the solution The ferrous salt is estimated in the usual manner Test analyses show the method to have a high degree of accuracy. H. W. Separation of Iron Aluminium Chromium Glucinum Titanium and Zirconium by the Sodium Carbonate Method. P. WENGER arid J. WURRMANN (Ann. ChLim. nnnl. 1919 [ii] 1. 337-339).-A method described previously by Wenger and Wunder (A. 1912 ii 687) may be applied when the mixture contains titanium or zirconium hut not both. After fusion with sodium carbonate the insoluble iron and zirconium oxides may be treated with hydrochloric acid (1 l ) in which the zirconium oxide is insoluble. I n the absence of zirconium iron and titanium may be separated by one of the known methods even in the presence of ghicinum.[See further .7. S'or.. P l i ~ w . Zn/7. 1920 4 6 ~ . ] w. P. s. A New Method for the Volumetric Estimation 01 Nickel. JOSEF HOLLWTA (Monntsli. 1919 40 281-291).-The process depends on the fact that when a nickel salt reacts with dimethyl- glyoxime acid is liberated which is estimated by titration with alkali in the presence of phenolphthalein or methyl-red. The standard iT / 50-solution is prepared by dissolving 4,6400 grams of pure dimethylglyoxime in the requisite quantity of 97:A alcohol (300-400 c.c.) ; 20 C.C. of AT-potassium hydroxide solution are added wihh constant shaking and the solution is diluted to 1000 C.C. with distilled water free from carbon dioxide and filtered after twenty-four hours from any slight precipitate of potassium carbonate.(The alcohol used must be free from aldehyde and neutral in reaction.) The alkali content of the solution is checked by titration with standard acid using phenolphthalein or methyl- red as indicator. The nickel solution under examinat.ion is diliitedii. 58 ABSTRACTS O F CHEMICL4L PAPERS. to the requiied extent a i d exactly iieutralised with N 10- or N / 5 0 - potassium hydroxide solution. 2-5 C.C. of the standard solution are added and after vigorous agitation the solution is gently warmed whereby the precipitate is caused to collect leaving a clear liquor ; the standard solution is then gradually added with frequent agitation until the solution acquires a permanent pale pink color- ation.I n consequence of the bulky nature of the nickel precipitate the amount of the metal in the solution should not exceed 0.03 gram. The method is particularly advantageous in dealing with very m a l l quantities of nickel and titration can readily be effected with X / 100-solutions if methyl-red is substituted for phenolphthalein as indicator. The results are not affected by the presence of the alkali salts of strong acids. Further details are promised in a subsequent communication. H. W. Iodometric Estimation of the Chromic Acid in Lead Chromate. MAX GROGER (Zeztsch. anorg. Chem. 1919 108 267-272) .-The iodometric method of estimating chromic acid has not hitherto been used for lead chromate on account of the impossi- bility of completely decomposing the chromate by means of dilute sulphuric acid.Dilute hydrochloric acid dissolves lead chromate completely but hydrochloric acid has a reducing action on chromic acid with liberation of free chlorine and has therefore not been used to dissolve lead chromate. It is now found however t h a t if the hydrochloric acid is sufficiently dilute its reducing action is negligible. Experiments showed t h a t when acid of 1.25N strength or less was used in the proportion of 25HC1 to 1 mol. of chromate no reduction took place after boiling the solution f o r three hours. With stronger hydrochloric acid the rate of reduction increased rapidly with the concentration of the acid. For carrying out an aualysis about 0.3 gram of lead chromate is dissolved in 50 C.C. of 1.25AV-hydrochloric acid by gently heating.The solution is cooled 1 gram of potassium iodide added allowed t o remain for ten minutes diluted with 100 C.C. of water and the free iodine titrated with sodium thiosulphate. There is no need to filter off the pre- cipitated lead iodide as the colour of this does not interfere with the end-point. After the end of the titration free iodine again appears after a short time. This is due to atmospheric oxidatiou of hydriodic acid a reaction which appears to be catalysed by the lead iodide present. The results obtained by this method are generally about 0.5% too high. Detection of Molybdenum by means of Xanthic Acid. J. KOPPEI (C’hem. Zeit. 1919 43 777-778).-Molybdenun1 com- pounds give a characteristic red to plum-coloured reaction with xanthic acid which was first described by Siewert (Zeitsch. ges.iYaturw. 1864 23 5). The test is preferably applied by acidify- ing the solution with a mineral acid after the addition of a trace of solid potassium xanthate. and is capable of detecting molybdenum in a solution containing 0~00000064 gram per c.c The reaction is E. H. R.ANALPTICAL CHEMISTRY. ii. 59 weaker when phosphoric formic or acetic acid is used for the acidification. and much weaker with salicylic acid whilst when oxalic citric or tartaric acid is used there is little if any color- ation. Analogous xanthic compounds are formed by copper iron cobalt nickel etc. but the colorations do not interfere with the molybdenum test. Vanadic acid forms a yellow compound and uranic acid a brown compound which like the molybdenum com- pound are soluble in ether and other organic solvents.Tungstic acid if present in very large preponderance may interfere with the test. The molybdenum compound may be obtained as a black oil by mixing a solution of 2 grams of ammonium paramolybdate with 1 gram of potassium xanthate. When vigorously stirred this oil solidifies forming black crystals with green surface reflections. The mean analyses of Siewert's solid preparation agree with the formula Mo0,,(OEt*C*S*S*H)2. [See also J . SOC. Cl~em. Zu(7. 1920 January.] C. A. M. Colour Reactions of Molybdenum and Tungsten. 11. G. A. BARBIERI ( A t t i R. Accnd. Lincei 1919 [vl 28 i 390-392. Compare A. 1919 i 549).-According t.0 Pkchard (A. 1894 ii 319). replacement of the hydrochloric or siilphuric acid used in Braun's reaction by acetic acid results in the formation of a yellow coloration and with concentrated solutions of a yellow. crystalline precipitate due to conversion of t.he molybdate into trimolybdate and union of this with the thiocyanate present to form an additive compound for instance KCNS,K20.3M00,,4H,0.On repetition o f PBchard's reaction with ammonium thiocyanate and ammonium permolybdate or tri- or tetra- or normal molybdate the author finds that in all cases the additive compound NH,SCN,(NH,),0,4Mo03,5H20 is formed and in no case an additive compound of the trimolybdate. From potassium trimolybdate and thiocyanate in presence of acetic acid the corresponding cornpozind KSCN,K,0,4Mo03,5H,0 is formed ; both potasium and ammonium compounds form yellow acicular crystals.Ammonium tetramolybdate. (NH4),0,4Mo0,:2~H,0 may be obtaiiied by the action of acetic acid on ammoilium permolybdato ill aqueous solution (compare Junius A 1905 ii. 826). T. H. P. Qualitative and Quantitative Test for Molybdenum in Steel and Iron. SIEGFRIED LAURENS MALOWAN (Zeitsch. anory. CILeni. 1919 108 73-80).-A specific and very sensitive test for molybdenum is given by xanthic acid. The test is best carried out with freshly prepared xanthate solution in the following manner. Absolute alcoholic potash is shaken with excess of carbon disulphide until no more of the latter is dissolved. To the solution so obtained 30% acetic acid is added until it shows a slight yellow turbidity and the reagent is added drop by drop to the solution t.0 be tested.If molybdenum is present an intense red colourii. 60 ABSTRACTS OF CHEMICAL PAPERS. develops which is quite stable in water and the intensity of which is proportional to the quantity of molybdenum present. The sensitiveness of the reaction is such t h a t 0.000005 gram of molybdenum in 0.00070/ solution can be detected with certainty in presence of ot$her elements. The coloured product is readily soluble in ethyl or amyl alcohol ether or chloroform less easily in petroleum and benzene. It is readily extracted from its reddish-violet ethereal solution by alkalis from which acids precipitate it. The ethereal solution decomposes on keeping with formation of molybdenum sulphide. The reaction is not given by vanadium tungsten titanium or uranium; chromates give a dark coloration with xaiithic acid and should be reduced if present before the test is made.The reaction can be used for the colorimetric estimation of molybdenum the coloured product being extracted with a mixture of 65Oh ether and 35% light petroleum and a mixture of 30% ether and 70% light petroleum used for dilution for comparison with the standard solution. If pure ether is used decomposition takes place too rapidly for accurate determinations to be made. E. H. R. Colorimetric Method for the Estimation of Small Quantities of Uranium. MULLER (Chem. Zezt. 1919 43 739-740) .-The method depends on the red coloration obtained when a uranyl salt is treated with sodium salicylate; the color- ation yielded by any uranyl salt solution is compared with t h a t produced by a known amount of uranium under the same coiidi- tions.Free mineral acid acetic acid iron alcohol or acetone must not be present but neutral alkali salts do not interfere. The method is suitable for the estimation of uranium in solutious con- taining as little as 0,0276 of the metal. w. P. s. Estimation of Zirconium by the Phosphate Method. G. E. F . LUNDELL and H. B. KNOWLES (1. Amer. Chen~. SOC. 1919 41 1801-1808).-Zirconium can be quantitatively pre- cipitated as secondary zirconium phosphate in cold or tepid soh- tions containing froin 2% t o 20% by weight of sulphuric acid pro- vided t h a t a ten- to one hundred-fold excess of the precipitant diaiumonium hydrogeij phosphate is used. Hydrolysis which occurs when the phosphate precipitate is washed with water can be almost entirely avoided by the use of a cold 5% ammonium nitrate solution for washing.Zirconium pyrophosphate for which the ZrO factor is 0.4632 is obtained on ignition of a secondary zirconium phosphate which has been washed with ammonium nitrate solution. No definite composition can be ascribed t o the com- pound resulting when secondary zirconium phosphate which has been mashed with water is ignited. Zirconium can be quantita- tively separated as phosphate in a 20% sulphuric acid solution from iron. aliiiniuinm chromium cerium. and thorium. The separatioll froin titanium Cali alio be effected provided hydrogen peroxide is p~eseiit. J . F. 8.ANALYTICAL CHEMISTRY. ii. 61 Gas-analytical Separation of Acetylene Ethylene and Benzene.W. D. TREADWELL and F. A. TAUBER (Hclv. Chim. A cta 1919 2 601-607).-The quantitative absorption of acetylene from mixtures containing it together with ethylene and benzene vapour is conveniently effected with a solution of mercuric cyanide (20 grams) in 2N-sodium hydroxide solution (100 c.c.) ; the gas is shaken with the mixture (6 c.c.) for one to two minutes a t the end of which the acetylene is completely absorbed whilst ethylene and benzene vapour are unaffected. A solution of mercuric nitrate (20 grams) in 2iT-iiitric acid (100 c.c.) which has been saturated with sodium nitrate is recom- mended for the absorption of ethylene in the presence of benzene vapour; the gas is shaken with 5-10 C.C. of the solution for two to three minutes. Propylene appears to behave similarly to ethylene since it is indifferent to alkaline mercuric cyanide solu- tion whilst readily absorbed by mercuric nitrate solution.H. W. Dehydrogenation of Hydrocarbons by means of Palladium-black. JENO TAWZ and NIKOLAUS VON PtrmoKY (Ber. 1919 52 [B] 1573-1583).-Zelinski has shown that cycle- hexanes are converted into benzene hydrocarbons by exposing them to the action of palladium-black a t 300° whereas hexane aiicl c!/cZopentanes are unchanged (A. 1913 i 167). This seemed to offer a process whereby cyclohexanes could be estimated in the presence of paraffins and a method has now been developed which gives satisfactory results within certain limits. The first difficulty to be overcome was the preparation of a sufficiently active catalyst for Zelinski’s agent is spoilt by mixtures of paraffins and cyclohexane long before the latter is completely dehydrogenated. I n the reduction of palladium solutions it is usual to employ formic acid any exceps being destroyed by the palladium-black itself.It seemed possible therefore that the activity of the catalyst would suffer in such a treatment and as it was found that the activity towards formic acid is parallel to the activity towards cyclohexane it was decided to use no more than the theoretical quantity of the reducing agent. This has the desired effect the catalyst being much more active. For example two specimens of 1 grain each prepared by Zelinski’s method pro- duced 1-8 and 11-2 C.C. of gas from formic acid but ten samples made by the new process which is described in detail gave 011 an average 458 c.c.one portion developing as much as 840 C.C. With such an active catalyst the quantitative dehydrogenation of c?/c/ohexane in various mixtures with hexnne may be easilv realised ; but then another disturbing factor appears namely that a t 300° the saturated paraffins themselves are to a certain extent converted into unsaturated hydrocarbons by palladium black. The sinall amount of hydrogen set free by the paraffins however reachw a constant volume after an hour or two and although a little more gas is liberated when the catalyst is renewed ail equilibriuinii. 62 ABSTRACTS OF CHEMICAL PAPERS is soon established. A similar equilibrium is reached when the olefines are heated with an excess of hydrogen t h a t is the hydrogenation is never quite complete. The volume of hydrogen produced by the paraffins is relatively small compared with the yield from the cyclohexanes so within certain limits the propor- tion of the latter hydrocarbons in a mixture can be gauged from the amount of hydrogen liberated.The limit is generally about 1% of cyclic hydrocarbon but in some experiments it was as low as 0.576. For mixtures containing less than this. only the chemical proof of the presence of benzene will suffice. The reaction with trioxymethylene and sulphuric acid is recommended. The catalyst (12 grams) is contained in a tube heated in a siniple electric furnace and the vapour is continually circulated. Thc volume of oil employed varies from 10 C.C. for rich mixtures to 100 C.C.I n the experiments described the following volumes of hydrogen were produced by 1 C.C. of hydrocarbon a t 300° (or 270O in the case of the methyl derivatives) cyclohexane 614 c c . ; methylryclohexane 618 C.C. ; 1 3-dimethylcyclohexane 504 C.C. ; ivopentane 38 C.C. ; n-hexane 40.8 C.C. (after renewing the catalyst five times) ; n-heptane 32.5 c c. ; n-octane 36 C.C. As an important application of the method the analysis of a sample of hexane b. p. 69-7Io from American petroleum is recorded. Whereas 30 c c. of synthetic n-hexane gave only 338 c.r. of hydrogen 30 C.C. of the natural oil yielded 446 C.C. under exactly the same conditions. This corresponds with 2.4% of cf/cZo- hexane in the sample and actually 0.5592 gram of pure dinitro- benzene was obtained from the dehydrogenated 30 C.C.of oil. For quantitative purposes a special apparatus is described. J. C. W. Criteria of the Degree of Purity of Commercial Toluene. JOHS SCOTT LT-NSDEN (T. 1919. 115 1366-1372). Differentiation of Methyl and Ethyl Alcohols. PANWWITZ (Ph arm. Zrntr.-h. 1919 60 441-442) .-Although crystallised copper sulphnte is insoluble in ethyl alcohol and dissolves in methyl alcohol t o give a blue solution this test is useless for dis- tinguishing methyl alcohol from ethyl alcohol. owing to the fact t h a t a small quantity of water destroys the blue colour of the methyl alcohol solution. The quantity of added water must be increased to 35% by vol. before the blue colonr reappears and a t this dilution ethyl alcohol also begins t o dissolve copper sulphate.The same effects are noticed when ferrous sulphate is used in place of copper sulphate. The borax flame test for methyl alcohol alio fails when water is present. w. P. s. Influence of the Presence of Trimethylene Glycol on the Estimation of Glycerol by the Zeisel isoPropyl Iodide Method. C. A. ROJAHN ( B e y . 1919,52 [B] 1454-1460).-AXlthough trimethylene glycol produces no silver iodide precipitate whenANALYTICAL CHEMISTRY. ii. 63 digested by itself in the Zeisel apparatus at 130-126° it does so behave when added to glycerol. In fact the excess of silver iodide corresponds with the amount of s-di-iodopropane produced if the quantity of trimethylene glycol is small. As a consequence Zeisel's method is not applicable to the estimation of fermentation glycerol (the German '' protol "-glycerol) for this contains tri- rnethylene glycol.J. C. W. Chromatic Reactions of Formaldehyde with certain Aromatic Compounds. ARTURO ROSSI (Boll. Chiin. Farm. 19 19 50 265-270).-Colorations which are not necessarily distinctive of the aldehyde are given by formaldehyde in 0.1 or 0.0Ol:A aqueous solution when added to sulphuric acid containing a trace of certain aromatic compounds in solution. Applied as a zone reac- tion the following colorations are obtained Gallic acid a reddish- brown ring and on shaking the tube a green liquid changing to greyish-green. Tanmc acid a reddish-brown ring and a liquid bluish- green a t the bottom but subsequently brownish-red throughout. Pyrogallol a light rose-coloured ring and liquid. The test is cap- able of detecting 0.00001% of formaldehyde.Salicylic acid a light rose-coloured ring and solution. CateciLol and resorcinol various red rings and liquids. P-NaphthoZ a violet-red ring and brownish- black liquid with green fluorescence. Belzzonaphf hoZ similar colour reactions. Phenyl salicylate carminered ring and reddish-yellow liquid becoming pink on dilution. Phenolphthalein no ring but an orange liquid changing to carmine-red on shaking. Dilution with water causes a carmine-red precipitate to separate. C . A. M. Estimation of Formaldehyde in Blood. E. SALKOWSKI (Biochem. Zeitsch. 1919 97 129-135).-The protein of the blood is hydrolysed with gastric juice. The hydrolysed mixture is dis- tilled and N/lO-iodine added to the distillate.The residual iodine is then titrated with thiosulphate. The formaldehyde found amounted to only 85.73% of the quantity added to the blood. 5. s. z. Estimation of Ace tone and Acetoacetic Acid with Auten- rieth's Colorimeter. H. SCHALL (Miinch. m d . Woch. 1919 66 812-814; from CJzem. Zentr. 1919 iv 562).-Description of the application of Autenrieth's colorimeter to the colorimetric estima- tion of acetone according to Legal and to the estimation of aceto- acetic acid. Gerhardt's iron chloride reaction is suitable for the estimation of considerable concentrations of the latter (above 0.5%)) whilst at greater dilutions Rimini's ethylenediamine test is used. The former has the advantage of easy manipulation and con- stancy of colour whilst the latter is more sensitive and gives a pure tint which however rapidly loses in intensity.Empirical solutions of dyes are used as standards. When acebone and acetoacetic acid are present simultaneously the estimation of acetone requiresii. 64 ABSTRACTS OF CHEMICAL PAPERS. the correctioii of a €actor since acetoacetic acid gives a positive I,egal’s reaction which is 5.55 as inteilse as that of acetone. H. W. An Acetoneurometer. A. ADLER (JIiiizch. med. Woch. 1919 66 722-723; from Chem. Z ( ~ r i t r . 1919 iv 398).-A colorimetric method of estimating acetoiie is described which is based on Legal’s test. -4 mixture of urine (10 c.c.) sodium hydroxide solution (20%) 1 c.c.) and sodium nitroprusside solution (33% 0.5 c.c.) is well shaken and acetic acid (20 drops) is added. The colour is compared with t h a t given by mixing Neutral-red New-blue and Diamond- phosphine.Solutions of the dyes of the following concentrations are piepared Neutral-red 1 1000; Xew-blue 1 1000; Diamond-phos- phine D 1 :loo. Ten C.C. of the first 3 C.C. of the second and 0’6 C.C. of the third solution are mixed with water 5 C.C. (solu- tion I) and correspond with 0.1% of acetone. Ten C.C. of solution I diluted with an equal volume of water correspond with 0.08% of acetone; 5 C.C. of solution I with 10 C.C. of water are equivalent in colour to 0.05% of acetone; 5 C.C. of solution I with 15 C.C. of water correspond with 0.01% of acetone. Five C.C. of a solution of neutral- red (10 c.c.) new-blue (1 c.c.) and diamond-phosphine (0.1 c.c.) with water (50 c.c.) correspond with 0’005% of acetone.The solu- tions are placed in tubes similar to those used in the experiment which are subsequently sealed. The five standards are in practice sufficient for ascertaining the acetone content of a urine. H. W. Methylene-blue as a Reagent for the Detection of Sugar in Urine. F. UTZ (Siiddeut. Apoth. Zeit. 1919 59 280-281 ; from CI’Lem. Zentr. 1919 iv 212-213).-According t o the author’s observations urines which contain sugar always give a positive reac- tion with solutions of methylene-blue even when Lieber’s modifica- tion of the test is used. Aqueous solutions of dextrose behave simi- larly but sucrose carbamide uric acid and saliva do not give the reaction. Milk behaves similarly to urine containing sugar. Whilst aqueous solutions of hexamethylenetetramine do not react with methylene-blue the urines of patients to whom the drug has been administered behaire similarly to saccharine urines but do not give a positive result with Fehlirig’s solution or Nylander’s reagent.Normal urines free from sugar also give a positive reaction with methylene-blue when they have been preserved for some days and are partly decomposed and this is particularly noticeable if they have been rendered alkaline with potassium hydroxide. Artificial gastric juice and glycuronic acid are also able to decolorise methylene-blue. The substance therefore is not a suitable reagent for the detectior of sugar in urine. Rapid Method for the Estimation of Sugar in Urine. OTTO MAYER (Arch. Hyg. 1919 88 184-197; from Chem. Zemtr.1919 iv 211-212).-The detection of sugar in urine is best carried out by Trommer’s test for the performance of which as also for Fehling’s and Nylander’s reactions practical directions are given. H. W.ANALYTICAL CHEMISTRY. ii. 6 3 The estimation of sugar is effected in the following manner urine ( 1 0 c.c.) is placed in a 100 C.C. stoppered measuring cylinder sodium hydroxide (1576 10 c.c.) is added and the solution is diluted t o 50 C.C. with water; copper sulphate solution (25 grains per litre) is gradually added with gentle shaking until the precipitate which denotes the end of the reaction practically completely redissolves ox vigorous agitation leaving only a just perceptible but permanent turbidity which slightly increases in course of time. Under these conditions each C.C.of copper sulphate solution corresponds with 0.1% of dextrose. If the urine contains more than 4O/ of sugar it is preferable to take only 5 c.c. whilst if the content is 0.5-17L 20 C.C. may be measured out. Separation of alkaline earth phos- phates from urines which have been treated with alkali and diluted from 2.5 to 10 times occurs only when these are present in excep- tional quantity. In this case since the sensitiveness of the elid- point may be greatly reduced it is advisable to treat 20 C.C. of the urine with 20 C.C. of sodium hydroxide solution to filter the solution after dilution to 100 c.c. and to perform the titration with 50 C.C. of the clear filtrate. For the detection of acetone powdered sodium nitroprusside (0.05-0.1 gram) is shaken with about 10 C.C.of urine about 1 C.C. of sodium hydroxide (15%) is added to the solution which is then acidified with acetic acid (3ci% 2 c.c.). I n this form the test is so sensitive t h a t distillation is only necessary with such urines as are deeply coloured or contain only small amounts of acetone. The most suitable reagent for the detection of acetoacetic acid is a mixture of liquor ferri. sesquichl. (5 c.c.) and sodium chloride solution (1 3 95 c.c.) the reaction being performed as a ring test. Volumetric Estimation of Sugar in Milk. J. L. JIAYER ( J . Amer. I’harm. Assoc. 1919 8 551-553).-BenedictJs method for the estimation of dextrose i n urine as modified by the author was applied to the estimation of lactose i n milk. The results were J.D] VAN LEEUWEN (Chem. ll’eekhlad 1919 16 1425-1426) .-In the titration of invert sugar solution with Fehling’s solution dilution of the latter with four times its volume of magnesium sulphate solution (0’5 gram per litre) causes the precipitated cuprous oxide to settle rapidly and thus gives a clear solution f o r testing with potassium ferrocyanide and acetic acid ; the solution must be cooled for this test. W. J. W. Estimation of Carbamide by means of Sodium Hypo- bromite. E. DEKEUWER and L. LESCOEUR (Compt. rend. SOC. Baol. 1919 82 445-447; from Chem. Zentr. 1919 iv 350).-In the estimation of pure carbamide by bromine and alkali hydroxide a slight deficit is always observed which has about the same magni- tude when calculated from the nitrogen evolved or from the bromine used; the error is doubled when the calculation is based on the H.W. trustworthy. CHEMICAL ABSTRACTS. [Estimation of Invert-sugar by Fehling’s Solution.]ii. 66 ABSTRACTS OF CHEMICAL PAPERS. amount of carbon dioxide formed. The course of the reaction appears to depend on the relative quantities of alkali and carb- amide. A factor can be applied based on the results obtained. I n the estimation of carbamide in urine high results are obtained when the calculation is based on the bromine which is utilised (particularly in the case of urines containing sugar) since bromine is also used in the oxidation of substances other than carbamide. The results deduced from the amounts of nitrogen and carbon dioxide formed respectively generally agree well among themselves ; in the case of urines containing sugar the values calculated from carbon dioxide are lower than those reckoned from nitrogen.11. m. Estimation of Carbamide in Blood and Urine. C. BRAHM (Deut. med. Woch. 1919 45 803; from Chent. Zetitr. 1919 iv 442).-A criticism of Citron’s method of estimating carb- amide. The latter is not quantitatively decomposed by sodium hypobromite according to the scheme CO(NH,),+ 3NaBrO = l3NaBr + CO + 2H20 + N since a proportion of the nitrogen is retained as nitric acid or cyanuric acid. I n the author’s opinion all methods which are based on the reaction between carbamide and sodium hypobromite are to be rejected. The form of apparatus proposed is also open t o many objections. H. IN. Estimation of Carbamide in Urine by means of Urease. ARNOLD HAHN (Deut.med. Woch. 1919 45 911-912); from Chem. Zenfr. 1919 iv 562-563).-The author’s method has been modified by Horvith and Kadletz by the introduction of a receiver containing acid ; the alteration is regarded as adding an unnecessary coniplication to the process. H. W. Detection of Hydrocyanic Acid in a Case of Poisoning. Its Post-mortem Transformation into Sulphocyanic Acid. k. CHELLE (Contpt. rend. 1919 169 862-854. Compare A. 1919 11 529 530) .-A dog was poisoned by administering potassium cymide and an autopsy immediately performed the various organs being divided up and kept in stoppered sterile flasks for various lengths of time. Using the methods previously described (Zoc. cit.) hydrocyanic acid as such but no thiocyanic acid was detected after two hours in the brain lungs and blood but not in the liver.After eight days no hydrocyanic acid as such could be detected in any of the organs or the blood but thiocyanic acid was found in the blood lungs and brain but not in the liver. Further the amount of thio- cyanic acid found in the lungs and brain but not in the blood corresponded with far more than the amount of hydrocyanic acid found a t the end of two hours. This is explained on the grounds that a certain amount of hydrocyanic acid becomes enclosed in the cells in the first few hours after death and is not set free by the methods of estimation used but after eight days as a result ofANALYTICAT CHEMISTRY. ii. 67 putrefaction and consequent cytolysis it is all liberated by the reagents and thus estimated. Estimation of Ferricyanide and Ferrocyanide.I. M. KOLTHOFF (Pharm. Weekblad 1919 56 1618-1626).-The author has invest.igated the iodometric estimation of potassium ferricyanide. The acidity of the solution has an appreciable influence on the reaction ; if the concentration is sufficiently high accurate results are obtained after allowing the solutions to remain for only half a minute. Rupp's method for the estimation of ferrocyanide is inac- curate. An outline is given of the theoretical interpretation of the iodometric estimation of ferri- and ferro-cyanide. The reducing action of ferrocyanide is increased by rise of temperature. W. J. W. W. G. Proteinogenous Amines. 11. A Micro-chemical Colori- metric Method for Estimating Iminazole Derivatives.KARL K. KOESSLER and MILTON T. &NKE ( J . Biol. Chem. 1919 39 497-519).-The method depends on the colour readion between compounds containing the iminazole ring and sodium p-diazobenzenesulghonate. It can be applied directly to practic- ally any iminazole derivative gives equally good results whether applied to pure solutions or mixtures and is capable of estimating with a fair degree of accuracy as little as 0.00001 gram of any of the iminazoles. The iminazole derivative is added under certain conditions to a mixture of sodium carbonate and the pdiazo- benzenesulphonic acid in one cup of a Duboscq colorimeter and the height of liquid in this cup is set a t 20 mm. The other cup is filled with an appropriate indicator solution and the height varied until the colours match.From tables which have been pre- pared the amount of the iminazole derivative can be read off. Certain substances interfere with the method notably ketones alcohols ammonium salts and proteins. Animal charcoal must not be used to decolorise solutions which it is desired to test for iminazole derivatives as loss by adsorption occurs. J. C. D. Proteinogenous Amines . 111. A Quantitative Method for Separating$ Histamine from Histidine. KARL K. KOESSLER and MILTON T. HANKE ( J . Biol. Chem. 1919 39 521-538).- The colorimetric process described in the preceding abstract may be utilised for estimating certain components of mixtures of iminazole derivatives. A mixture oQ these derivatives such for example as that which is formed by the action of bacteria on histidine in the presence of salts and dextrose is treated with sufficient sodium hydroxide to make the whole a 20% solution of alkali.This solution is extracted repeatedly with amyl alcohol whereby the histamine ammonia methyliminazole and other amines are removed. This extract is termed the histamine frac- tion whilst the residual liquid containing histidine iminazole pro- pionic acetic and lactic acids is called the histidine fraction. The amount of histidine can be determined by an estimation of theii. 68 ABSTRACTS OF UHEMICAL PAPERS. amino-nitrogen in the second fraction. A colorimetric estimation on the same fraction will indicate whether there are other iminazole derivatives present other than histjdine. The histamine and methyliminazole are extracted from the amyl alcohol by 1 *ON-sulphuric acid and a colorimetric estimation will give on this extract an indication of the total iminazole sub- stances present.The methyliminazole may be estimated directly by the fact that it is volatile in steam. The colorimetric estimations on these two fractions will give by difference the amount of histamine present. J. C. D. Direct Estimation of Non-amino-nitrogen in the Products of Protein Hydrolysis. ALMA HILLER and DONALD D. VAN SLYRE ( J . Biol. Chem. 1919 39 479-488).-An extension of the method of protein analysis introduced by Van Slyke (A. 1915 ii 851). The filtrate from the phosphotungstates of the diamino-acids repre- senting 2 or 3 grams of protein is concentrated to 150 C.C. Por- tions of this solution are used for estimations of the total nitrogen and amino-nitrogen as described in the original paper. Of the residue 100 C.C. are measured into a separating funnel of 500 C.C. capacity and are rendered free from phosphotungstic acid by extraction with amyl alcohol-ether mixture in the presence of hydrochloric acid. The solution is concentrated in a vacuum to about 50 c.c. and washed into a 100 C.C. volumetric flask. Of this solution 20 C.C. portions are used for the non-amino-nitrogen nstimation. Each portion is placed in a small Kjeldahl flask with 1-2 C.C. of 30% sodium nitrite and 5 C.C. of concentrated hydro- chloric acid. When deamination is completed the solution is neutralised to alizarin with 10% sodium hydroxide and reduced with zinc-copper couple. After making alkaline with magnesium oxide the ammonia formed by the reduction is removed by boiling and residual nitrogen is estimated by the Kjeldahl process. The results by this direct method agreed closely in analyses of caseinogen and gelatin with the results obtained indirectly by the original procedure. J. C. D. Apparatus for Rapid Gastric Analysis together with a Method for the Preservation of Starch Solution. RAYMOND J. MILLER ( J . Znd. Eng. Chem. 1919 11 963-964).-A con- venient arrangement of burettes indicator reservoirs and delivery tubes an automatic pipette etc. attached to one stand and intended for the estimation of total acidity free acidity and amino-acid nitrogen (formaldehyde method) in gastric fluids. The starch solution is preserved under a laper of liquid “petrolatum,” with or without the addition of a small quantity of toluene. w. P. s.

ISSN:0368-1769    

DOI:10.1039/CA9201805047

出版商:RSC    

年代:1920

数据来源: RSC

摘要:

fi. 69 General and Physical Chemistry. The Constitution of the Atom and the Properties of Band Spectra. H. DESLANDRES (Compt. rend. 1919 169 1365-1371. Compare A 1919 ii 206 310 441 486).-Further evidence is given in support of the views previously published (Zoc. c i t . ) . The author emphasises the fact that the formula given (A 1919 ii 206 310) is only a first approximation and offers some explanation of the divergencies found in certain cases. W. G. Intensity Relations in the Spectrum of Helium. T. R. MERTON and J. W. NICHOLSON ( P ? d . Trans. 1919 A 220 137-173).-The spectrum of helium has been examined by photo- graphing the radiation in front of an aluminium cathode in a tube containing helium of such a pressure that the thickness of the dark space was about 1 mm.A number of experiments were made with mixtures of helium and other gases particularly hydrogen. The most striking phenomenon observed relates to the difference in behaviour between the series of helium and parhelium for in the former lines belonging to a series maintain a practically constant intensity ratio a t every point whilst in the latter the relative intensity of any two lines of the same series variea with the distance from the cathode. I n the case of lines belonging to the principal series the seat of maximum emission is closer to the cathode and falls away with increasing distance from this point more rapidly than in the case of lines belonging to associated series. The diffuse series appear to preserve the most uniform intensity over a wide range of conditions. J.I?. S. F. PASCHEN (Ann. Physik 1919 Pv] 60 405-453).-An account is given of a very complete examma- tion of the spectrum of neon from A 9840.42 to A 2550’55. A long table is given of the wavelengths intensities and the spectrum combination of each line. The regularities between the lines of the principal and subsidiary series are investigated and discussed. Spectrum of Neon. J. F. S. Emission Spectra and the Chemical Reactions taking place in thesource of Radiation. ANGEL DEL CAYPO (Anal. Fis. Quim. 1919 17 247-27O).-Attention is directed to slight variations in the spectrum of the same element as described by different observers. The author regards these as being due to chemical reactions notably oxidation and reduction occurring within the radiant arc.These reactions may be localised according to circumstances in the immediate neighboyrhood of the electrodes or in the middle of the arc itself thus giving rise to a pol^ effect” in the photograph. This is illustrated in the w e of the VOL. OXVIII. ii. 3ii. 70 ABSTRACTS OF CHEMICAL PAPERS. silioa spectrum which shows variations it9 different sections of the arc between the carbon electrodes are examined. The view is expressed that the variations are due to the presence or absence of a reduction product the suboxide SiO. A similar phenomenon is observed with magnesium and is attributed to the suboxide Mg,O. I n studying the spectra of various specimens of aragonite three new lines 2554.6 2563.8 and 2565.0 A.U. were observed. These were given by all samples of naturally ocaurring calcium carbonate examined but not by pure hydroxide.In both cases the oxide formed is reduced to metal in contact with the carbon. This is immediately re-oxidised in the arc but in the former case the pro- tective action of the carbon dioxide liberated a t the same time ensures the persistence of the metallic vapour for a longer time and range so that the radiation from the metal is rendered perceptible. Further experiments confirmed the view that the lines in question belong to the calcium spectrum and are not due to impurities in the substances examined. W. S. M. The Emission of Positive Luminous Particles at High Temperatures by the Alkali Metals. G. A. HEMSALECH (Compt. rend. 1920 170 44-47).-Using the graphite plate with a layer of carborundum the plate being electrically heated as previously described (compare this vol.ii 1 2) it is shown that if the plate is first covered with a thin layer of the chloride carbon- ate or oxide of one of the alkali metals and this in turn covered with carborundum positively electrified particles are emitted a t varying temperatures. All the elements in the alkali group emit positive particles and for a given temperature the exten- sion and development of the luminous trajectories vary directly with the atomic weights and in consequence the critical tempera- ture or temperature a t which the phenomenon is apparent varies inversely with the atomic weight. For lithium the critical tempera- ture is 2700° and for caesium 1900O. Two hypotheses are put forward to explain this phenomenon but further work is necessary before a definite explanation can be given.[The Emission of Positive Luminous Particles at High Temperaturea by the Alkali Metals.] A. DE GRAMONT (Compt. rend. 1920 170 47).-The author states that Hemsalech used a monochromatic optical pyrometer for the temperature measure- men& in his work (preceding abstract). The instrument was Cali- brated and corrected up to 2500° above which temperature extra- polation was necessary. A t 2700O the temperature readings are accurate to *50°. W. G. The Direct Arc Spectra of Metals with Moderately High Melting Points A. DE GRAMONT (Compt. rend. 1920,170,31-%).- A comparison of the direct arc spectra with the spark spectra and the carbon arc spectra in the case of the metals zinc cadmium tin lead antimony bismuth magnesium and aluminium.By the photographic device employed the three spectra were obtained in W. G.GENERdL BND PHYSICAL CHEMISTRY. ii. 71 successive coincidence thus permitting of a direct comparison of the rays. By this means it has been possible to detect in the direct ray spectra on the one hand certain rays of the spark spectra considered by Lockyer as strengthened and which occur in the direct spectra with a marked intensity and on the other certain rays of the spark spectra also classed as strengthened but which are only fugitive in the direct arc spectra. The latter group of rays appears at the positive pole at the moment of striking the arc. They can most easily be seen by alternately making and breaking the arc.The detailed results are given for each of the metals and the general conclusions to be drawn are that the arc spectra must not be considered as invariable and always identical. They are subject to considerable variations not only in the intensi- ties of certain rays but also in the appearance of the rays these variations being closely connected with the intensity of the current producing the arc. W. G. New L i e s in the Arc Spectrum of Silver between X 4500 and X 2300. M. A. CATAL~N (Anal. Fis. QuinL. 1917 15 483486).-Measurements of eighty new lines were made with wave-lengths corresponding with similar lines in the spark spectrum described by Exner and Haschek (“Tabellen der Funkenlinien,” 1902). W. S. M. New Lines in the Arc Spectrum in Air of Iron between 2300 and 1980 A.U.S. PIBA DE RUBIES (Aizal. Fis. Quim. 1917 15 434444).-Measurements of more than 288 new lines in the arc spectrum of iron are given extending the spectrum from 2300 A.U. to 1994 A.U. W. S. M. New Lines in the Arc Spectra of Nickel and Cobalt between 2300 and 2000.&.U. S. PIRA DE RUBIES ( d i d Fis. Quim. 1918 16 338-350).-A total of 66 new lines f o r nickel and 165 for cobalt in the given range was measured. CARL RENZ (Helw. Chim. Acta 1919 2 704-717).-The action of light on thallous chloride has been investigated; the action was carried out with the dry substance and with thallous chloride under water hydro- chloric acid ammonia ethylamine ethyl alcohol glycerol toluene xylene and pyridine. I n all cases a darkening occurs which passes through the shades greyish-brown dark greyish-brown and blackish-brown.The change is due to the formation of a photo- thallous chloride and thallous-thallic chloride. Hydrochloric acid even in trams retards the formation of the photo-chloride and after prolonged illumination various yellow double thallous-thallic chlorides are formed. Nitric acid and sulphuric acid have a similar retarding action on the formation of the photo-chloride. Ammonia ethylamine and the abov*named organic substances act as semi. tisers in the reaction and many inorganic salts have a photo W. S. M. Photochemistry of Thallous Chloride. 3-2ii. 72 catalytic action. The sensitiveness of thallous chloride to light depends on its method of formation. Thallous chloride precipitated by metal chlorides is more sensitive than that precipitated with hydrochloric acid even though the acid has been thoroughly washed out. J.F. S. ABSTRACTS OF CHEMICAL PAPERS. Diffusion of Radium Emanation in Water. EVA RAMSTEDT (Medd. K . Vetenskapsakad. iVobel-lnst. 1919 5 No. 5 1-14).- The velocity of diffusion of radium emanation in water a t 14O has been determined by means of an apparatus containing a number of metal plates immersed in water. The coefficient of diffusion is found to be 0.820 cm. per day a value which is of the same dimensions (0,985 a t 18O) as that recently found by Rona (A. 1917 ii 286). Calculating from this value the product D& is found to be 12.2 and the molecular diameter of radium emanation 1'85 x 10-8 cm. J. F. S. Ionisation Potential of Helium.J. FRANCK and P. XNIPPING (Physikal. Zeitsch. 1919 20 481-488) .-Using as source of electrons a glowing wire in helium of pressure 1.5 mm. the reson- ance potential is found to have the value 20.5-10.25 volts and from this value the ionisation potential is calculated to 25.3k0.25 volts. Experimentally the ionisation potential of helium is found to be 25.41t0.25 volts and the resonance potential has the same value as before. The potential necessary for the removal of both electrons from the helium atom is also determined and the value 79.5rt0.3 volts obtained. The present results are in agreement with those of Horton and Davies (A 1919 ii 210) and indicate thaf. the helium atom is much less stable than is indicated by the atomic model of Bohr and LandQ.J. F. S. Conductivity. VI. Behaviour of Mixtures of Two Salts containing a Common Ion in Anhydrous Formic Acid Solution. H. I. SCHLESINGXR and F. H. REED (J. Amer. Chem. SOC. 1919 41 1921-1934. Compare A 1919 ii 91).-The con- ductivity of potassium f ormate in anhydrous formic acid solution has been determined a t ' 2 5 O over the range 0.1207N-0*3266hT. The degree of ionisation and the ionisation constant are caloulated in each case and the latter constant has the value 1.090. Similar measurements were also made f o r sodium formate and lithium formate; these salts have ionisation constants 0'810 and 0.557 respectively. Conductivity measurements were also made for mixed solutions of sodium and potassium formates lithium and potassium formates strontium and potassium formates and strontium and calcium formates all in anhydrous formic acid and a t 25O.A method of calculating from the ionisation constants the degree of ionisation of each of two salts containing a common ion when the two salts are both present in solution has been developed for the case in which both salts obey the law of mass action. It is found that in mixtures of sodiunl and potassium formates asGENERAL AND FHYSICAL CHEMISTRY. ii. 73 well as of lithium and potassium formates the mass law is obeyed by both of the highly ionised salts present. On the other hand solutions of mixtures containing as one or as both of the salts alkaline eart,h formates do not conform to the law although these uni-bivalent salts when in solution alone seem to follow the law over a certain range of concentration.This appears to make it quite certain that whenever the agreement of the salt with the law is an accidental one solutions of mixtures containing such a salt will not obey the law. Hence it may be definitely concluded that the agreement between the behaviour of the alkali met,al formates in anhydrous formic acid solution and the demands of the mass law is a real and not an accidental one. When the total concentration of mixed solutions becomes relatively great deviation from the mass law occurs also i n the solutions which contain uni- univalent formates. It has been found that this deviation begins when the concentration of the nan-ionised molecules of one of the salts reaches the same value as that a t which deviation begins in the solution of that salt by itself.This seems to be independent of the concentration of the other molecular species present and to indicate that in concentrated solutions it is the non-ionised mole- cules and not the ions which cause deviation from the mass law or a t least the non-ionised molecules cause deviation a t lower concentrations than do the ions. J. F. 5. Conductivity. VII. Transference Numbers of the Formates of Sodium Potassium and Calcium in Anhy- drous Formic Acid. H. I. SCHLESINGER and E. N. RUNTINQ ( J . Amer. Chem. SOC. 1919 41 1934-1945. Compare preceding abstract) .-The transport numbers of solutions of sodium potassium and calcium formate in anhydrous formic acid have been determined by the usual method a t 2 5 O for a number of con- centrations between 0.09N and 0.4N.The ionic conductivity of the formate ion is calculated t o be 51.5 that of sodium ion 14.6 and potassium 17.5. The transport number of the potassium ion changes with concentration. This is tentatively explained on the assumption that the ion is solvated and a method for calculating the extent of solvation from the transport numbers is suggested. The results indicate that if the assumptions made in the calcula- tion are correct each potassium ion is combined with from six to eight molecules of formic acid. The transport numbers obtained for calcium formate do not substantiate1 the view that calcium formate in formic acid solution ionises either entirely as a uni- univalent salt or ent$irely as a uni-bivalent salt.It is therefore possible that both methods of ionisation occur. Electric Conductivity of Weakly Ionised Neutral Salts. OLOF SVANBERG (Medd. K . Ventenslzapsakad. Nobel-Tnst. 1918 3 No. 26 1-7).-The equivalent conductivity of potassium antimony1 tartrate and cupric acetate has been determined over the range N / 4 to N/1024 a t temperatures 0-65O. I n the case of potassium anti- rronyl tartrate the equivalent conductivity increases fram 64.4 at J. F. S.ii. 74 ABSTRACTS OF CREMICAL PAPERS. d = 4 to 134.5 a t d=1024 a t 25O; the more concentrated solutions (up to N/32) a t all temperatures follow the Ostwald dilution law but beyond this point the conductivity increases more rapidly than is demanded by any of the formuls for the extrapolation of the infinity value.There is no evidence that potassium antimony1 tartrate ionises as the potassium salt of antimonyl tartaric acid and it is also shown that the salt is not greatly hydrolysed in any of the solutions examined. I n the case of cupric acetate the equivalent conductivity a t 25O increases from 10.8 in N-solutions to 75.3 in N / 1024 solutions which indicates considerable hydrolysis. The equivalent conductivity a t infinite dilution has been obtained by extrapolation and the following values found potassium antimonyl tartrate Oo A = 76 ; 25O A = 154 ; SO0 A = 260 ; 65O A = 308 copper acetate 2 5 O A =90. J. F. S. Relation between the Electrical Phenomenon in Cloud- like Condensed Odorous Water Vapours and Smell- intensity. H. ZWAARDEMAKER and H. ZEEHUISEN (Proc.K. Akad. Wetensch. Amsterdam 1919 22 175-178).-0dorous organic sub- stances in dilute aqueous solution when sprayed yield electric charges. It is found on diluting these solutions to such an extent that the electrical phenomena are only just appreciable that the odour is also just appreciable. It is suggested that both these properties depend in a complicated way on (u) the volatility of the substances and (a) the lowering of the surface tension of the solvent (compare A. 1918 ii 351). J. F. S. Dielectric Constants considered in Connexion with the Theory of Dipolar Molecules. OSKAR RLEIN (Medd. K. Vetenskapsakad. Nobel-lnst. 1918 3 No. 24 1-48).-The dielee- tric constants have been determined for a number of solutions in organic liquids by means of a resonance method.The solutions examined consisted of (1) methyl alcohol ethyl alcohol propyl alcohol butyl alcohol amyl alcohol ally1 alcohol benzyl alcohol acetone and methyl ethyl ketone in benzene; (2) ethyl alcohol butyl alcohol and benzyl alcohol in chloroform. It is shown that the resonance method which is the method used technically for measuring capacity is well suited to the measurement of dielectric constants. Solutions of the alcohols in benzene or chloroform of the same normality have the same dielectric constant. Thus N-solutions of alcohols in benzene have a dielectric constant 2.63 in chloroform solution 5-68. Acetone and methyl ethyl ketone have the same value in benzene solution namely 3-09. J. J. Thornson’s rule that related substances have the same value for ( e - 1)M holds absolutely for mixtures of the alcohols and water.Some measurements of Pohrt on the dielectric constants of gases are examined and yield the temperaturecoefficient which is demanded by the dipolar theory. The formula of Debye ( e - 1) / ( e + 2) . v = A / T + B is changed t o the form ( e - l)(w - b ) = A /T in which for substances which belong t o a single group the relationship A M = L obtains ; I is a constant pro-GENERAL AND PHYSICAL CHEMISTRY. ii. 75 portional to the square of the molecular moment and M is the molecular weight. These formulz combine the above-named rules and are in keeping with the dipolar theory. The constant L has been calculated from several of the experiments and the values for alcohol (67,000) and acetone (180,000) obtained.The formula ( e - 1) = A / T(v - b ) is applied to the dependence of the dielectric constant on temperature in the case of water and found to be in keeping with fads. The formula K=L/T=M(u- b ) ( e o - l ) + p / [ l + k(e0- l)] holds for infinitely dilute solutions and together with (C - 1) = A / (v - b)T' furnishes an exact method for calculating the constants IC and b. The approximate formula R = p / [ ( l + k(eo-l)] is deduced from the above and allows the determination of R from a knowledge of the dielectric constant of solutions of the substances concerned. J. F. S. Dielectric Constants of Typical Aliphatic and Aromatic Hydrocarbons cycloHexane cycloHexanone and cyclo- Hexanol. THEODORE W. RICHARDS and J. W. SHIPLEY (J. Amer. Clienz. SOC. 1919 41 2002-2012).-The dielectric constants of a ncmber of hydrocarbons have been determined at 20° except in the case of cyclohexanol which was determined a t 25O by a modified Nernst type of apparatus.The percentage error of the method wa5 much decreased by the use of larger suitably balanced condenser troughs. The following values have been obtained as the mean of several concordant measurements hexane 1.876 ; heptane 1.973 ; obtane 1'962 ; n-nonane 1.967 ; B-methyloctane 1.967 ; 8-methyl- octane 1.967 ; B<-dimethylheptane 1.987 ; flB-dimethylheptane 1.89; Be-dimethylheptane 1.89; decane 1.956; xylene (com- mercial) 2.375 ; m-xylene 2.377 ; ethylbenzene 2.482 ; n-propyl- benzene 2.364; cumene 2.400; mesitylene 2.356; tert.-butyl- benzene 2.384 ; cyclohexane 2.055 ; cyclohexanone 18.2 ; and cyclo- hexanol 15.0.The present results are in moderate agreement with the values of previous observers although in many cases no previous measurement is on record. Relation between the Specific Inductive Capacity of an Electrolyte and the Electric Potential of a Metal placed in it. D. L. ULREY (Physical Rev. 1919 12 47-58).-Attention i 4 called to the inadequacy of the Nernst theory of the mechanism of galvanic current production. This theory omits an essential factor namely specific inductive capacity of the electrolyte and employs two hypothetical quantities metal solution pressure and osmotic pressure of the ions. Transfer of ions between metal and electrolyte is probably brought about by electrical forces the magnitude of which depends on the specific inductive capacity of the medium.The potential difference between electrodes of the same kind ,in a two-solution cell was measured for several different percentage mixtures of two liquids for four different cases and in each case was shown to be strictly proportional to the difference in the specific inductive capacity of the two solutions. The following systems were measured (u) ethyl alcohol-water (solution of cupric J. F. S.ii. 76 ABSTRACTS OF CHEMICAL. PAPERS. chloride) with copper electrodes (electrode in the aqueous solution electronegative) ; ( h ) ethyl alcohol-water with calomel electrodes (electrode in the water electropositive) ; (c) acetone water with calomel electrodes (electrode in the water electropositive) ; ( d ) methyl alcohol-water with calomel elee trodes (electrode in the water electropositive) ; and ( e ) solution of carbamide-water with platinum electrodes (electrode in the water electropositive).I n two cases investigated with copper elec- trodes one with platinum electrodes and six with calomel electrodes the direction of the E.M.P. of the cell is in accordance with the theory that the loss of ions from an electrode ia dependent on the specific inductive capacity of the electrolyte rather than on the concentration of those ions in the electrolyte and a solution tension of the electrode. Results obtained further substantiate the theory that the more electropositive metals have the higher specific inductive capacities. Changes of Potential in an Oxidising Agent by Ultra- violet Light.TORSTEN SWENSSON (Arkiv. Kern. Mzn. Geol. 1917 6 No. 12 1-32).-The effect of ultra-violet light on the potential of solutions of potassium dichromate in sulphuric acid has been examined. The souroe of light employed was a quartz mercury lamp and the solutions were maintained at 1 8 O during illumina- tion. The platinum electrode used in the measurements was bright since it was found that the same value was obtained with both bright and platinised electrodes but the former reached equiLi- brium more rapidly. It is shown that during the illumination with ultra-violet light of a solution of potassium dichromate and sul- phurio acid and also during the illumination of either sulphuric acid potassium dichromate or chromic acid alone a change in potential occurs.To achieve this result it is not necessary to illu- minate the platinum electrode. In the case of dichromate and sulphurio acid a speedy increase in the potential occurs ; whilst when sulphuric acid and dichromate are illuminated separately a decrease in potential occurs. The potential is also decreased f o r pure chromic acid and consequently it is shown that the positive effect does not depend on the liberation of this acid on the addition of sulphuric acid to the dichromate. The speedy change in E.M.F. is caused by the ultra-violet rays and is not observed when the action takes place in glass vessels. Both the increase and decrease of E.M.F. are of a photachemical nature. Over the rangeexamined the potential change is independent of dilution.The change of potential is in a high degree dependent on the composition of the solution and shows a maximum a t about 75 mol. % potassium dichromate. The decrease in E’.Jf.F. after the interruption of the illumination takes place gradually. It is also dependent on the com- position and is most rapid for pure sulphuric acid. It is further greatly dependent on the temperature and after a moment’s boiling the potential becomes normal again. Solutions which have been illuminated but have returned to their original potential show on renewed illumination changes in the velocity of the potential CHEMICAL ABSTRACTS.GENERAL AND PHYSICAL CHEMISTRY. ii. 77 increase and the maximum value. On very bright illumination a rapid increase i n E.il1.E’. was observed which on interruption of the light sank very quickly. I n this case the illumination of the electrode is essential.J. F. S. Polarisation Tensions of Iron in Solutions of its Complex Salts. Relations between these Tensions and the Dis- simulation of Analytical Characters of Ferric Ions. N. R. DHAFL and G. URBAIN (Compt. rend. 1919 169 1395-1397).- The electrolytic cell consists of two half elements joined by a solu- tion of potassium chloride. One half element consists of a metallic electrode i n a solution of one of its salts and the other is an elec- trode of mercury in a solution of calomel and potassium chloride. The polarisation tension is defined as the difference between the E.M.F. of the whole cell and the corresponding value as found i n Auerbach’s results (compare A.1912 ii 123) for the half element containing the mercury electrode. This tension should depend on the number of free metallic ions in the solution the tension diminishing as the number of ions increases. These measurements should therefore in the case of complex salts give an indication as to how f a r the metallic constituent of the complex ion is dissimu- lated. The results obtained with simple and complex iron salts are in agreement with those obtained by Pascal (A 1909 ii 487) as to their molecular magnetic susceptibilities. Hydrogen Overvoltage. 11. Applications of its Variation with Pressure to Reduction Metal Solution and Deposition. D. A. MACINNES and A. W. CONTIERI ( J . Amer. Chem. SOC. 1919 41 2013-2019. Compare A. 1919 ii 131).-The increase of hydrogen over-voltage with diminished pressure is shown t o follow i n a nearly quantitative manner from the theory of MacInnes and Adler (Zoc.cit.). The effect of a change in the gaseous pressure on several chemical processes involving the evolution of hydrogen has been studied. The changes i n rates of reaction and in reaction efficiencies were found in each case to be in the directions which follow from the change of hydrogen over-voltage with pressure; t h a t is a decrease of gaseous pressure produces (a) a decrease in the rate of solution of metals i n electrolytes ( b ) an increase i n the efficiency of reductions by metals and (c) an increased efficiency of metal deposition. The theory explaining the fluctuation of over- voltage accompanying the evolution of a single bubble of hydrogen from a platinum electrode is discussed. Determination of the Hydrogen Exponent.J. PINKHOF (Chem. Weekblad 1919 16 1168-1172).-1f in Poggendorff’s method the normal electrode is replaced by an electrode which does not differ in potential from t h a t of the hydrogen electrode then if the composition of the liquid is known and it.s relation t o the potential the potential of the hydrogen electrode and there- fore the hydrogen exponent can be determined. The results obtained with a silver electrode in a solution of silver cyanide in W. G. J. F. S. 3*ii. 78 ABSTRACTS OF UHEMICAL PAPERS. excess of potassium cyanide were not accurate. An electrode of cadmium amalgam in solutions of cadmium salt of various concen- trations was found to be suitable.A simple apparatus for the determination is described. W. J. W. Applicability of the Gas Law6 to the Strong Electrolytes. J. N. BRONSTED (Medd. R. Vetenskapsakd. Nohel-Inst. 1919 5 No. 25 1 4 9 ) . - A npmber of solubility and E.M.F. measurements have been carried out with the object of testing the hypothesis. "The gas laws hold for ions or salts when other salt solutions are employed as solvents the concentration of the latter being large when compared with the concentration of the dissolved salt." The E.M.F. of cadmium [ cadmium sulphate in magnesium sulphate solution has been measured. ( m n a l g % 3 * 1 % ) ' ~ ~ i ~ ~ ~ ~ ~ i o l . ! iMgso,(2 CdS04 - clMol* cl) mol. 1 (amalgam 3.1%) The value of c and c1 varied between 0'1M and 1/64OM and the temperature was 20° and 39.40.The potentials obtained are compared with those demanded by the gas laws and an excellent agreement found. The solubility of dinitrotetra-amminecobalt nitrate both a and B varieties has been determined at Oo and 20° in water and in solutions of various concentrations of potassium formate thiocyanate hydroxide and nitrate nitric acid scdium oxalate and sodium nitrate. The values obtained are in keeping with the demands of the gas laws. The Electroaffinity of Aluminium. I. The Ionisation and Hydrolysis of Aluminium Chloride. 11. The Aluminium Electrode JAROSLAV HEYROVSK~ (T. 1920 117 Occlusion of Hydrogen and Oxygen by Metal Electrodes. EDGAR NBWBERY (1. Amer. Chem. Sac. 1919 41 1887-1892 1895-1898); EARLE A. HARDING and DONALD P.SMITH (ibid. 1892-1894 1897-1898) .-Polemical. In the first paper Newbery gives a theoretical discussion of the paper put forward by Harding and Smith (A. 1918 ii 424) and a criticism of the theory put forward as to the condition of the occluded hydrogen in palladium. The following papers cont.ain replies and counter-replies by Harding and Smith and Newbery. J. F. S. Electro- and Thermo-chemical Investigation of the ,Cells Cu or Cu Amalgam I CuS0,-Hg,S04 I Hg. L. W. OHOLM (Medd. K . Vetemskapsakad. Nobel-Inst. 1919 5 No. 4 1-20). -The E.M.F. of the elements Cul N-CuSO,,Hg,SO,(sat.) 1 Hg and Cu(12% amalgam) I N-CuS0,,Hg2S04(sat.) 1 Hg have been measured a t 100 15O 17O 200 250 and 30° daily for a period of two months. The copper amalgam cells are fairly constant and easily repro- ducible and the variation of the E.M.F.with temperature is represented by the formula The cells with a copper electrode had a slightly higher (0*004-0~005 The element is made up Cd J. F. S. 11-26 27-36). Et= 0'35030 - 0*00064(t - 20) - 0'0000025(t- 20)'.GENERAL AND PHYSICAL CHEMISTRY. ii. 79 volt) E.M.P. than the amalgam cells and it is nothing like so constant. The chemical energy of the copper cell is calculated and the value Q =24,860 cal. obtained. The quantity Q is regarded as made up of three quantities ql x2 and q3 q1 being the heat change when 1 gram- atom of copper is withdrawn from the amalgam qz the difference in the heat of formation of copper and mercury sulphate and q3 the heat change accompanying the withdrawal of water from the solu- tion by the newly formed copper sulphate.These three values are calculated to pi= - 1297 Gal. at 20° q,=7600 Cal. and q,=18.527 Cal . J. F. S. HORACE G. BYERS and CURTIS W. KING (1. A m e r . Chem. SOC. 1919 41 1902-1908).-When cobalt is used as anode in the electrolysis of 0.02N-sulphuric acid or sodium sulphate a t Oo it becomes passive if a high current density is employed but with low current density it remains active; if potassium dichromate is present it readily assumes the passive con- dition in all circumstances. The passive state is indicated by an increased drop in potential a decreased current by the evolution of oxygen and by the failure of the cobalt t o pass into solutiou. The potential measurements of a cobalt-platinum cell with various electrolytes and a comparison with similar results with iron and nickcl show that when the cobalt becomes passive t.here is a marked increase in voltage across the cell.The potential measurements show that this is due to a change in the potential of cobalt as it changes from the active to the passive condition. Cobalt may therefore be classified with the passive metals since it exhibits all the characteristics of iron and nickel when they are passive. The essential difference between cobalt and the other passive metals lies in the fact that cobalt when used as an anode will not become passive a t the low current densities required by nickel and iron. If cobalt has once assumed the passive condition it will remain so even though the current density is reduced.I n ths absence of the anodic relation cobalt becomes active in acid solution more readily than nickel. Activity Coefficient for Ions. NIELS BJERRUM (&?kid. K. Vetenskapsakad. Nobel-lnst. 1919 5 No. 16 1-21).-A theoretical paper in which activity coefficients are considered with the object of bringing strong electrolytes into line with the ionic hypothesis. The activity coefficient is defined as the effect of the interionic forces on the activity of the ions the conductivity coefficient as the influence of the interionic forces on the con- ductivity and the osmotic coefficient as the influence of the inter- ionic forces on the osmotic pressure. Various relationships between these and other similar coefficients are evolved mathematically. E =0*3542 and dEjdT = - 0.000'72 volt.Passivity of Cobalt. J. F. S. J. F. S. Comparative Electrolysis of Various Alkali Chlorides. E. BRINER (MLLE.) A. TYROCINER and B. ALFIMOFF (Helw. Chim. -4cta 1919 2 666-672).-Solutions of the chlorides of sodium 3'-2ii. 80 ABSTRACTS OF CHEMICAL PAPERS. lithium and potassium of various concentrations have been electro- lysed and the relative current yields of alkali hydroxide compared. After the passage of 50,000 coulombs through 3'lN-solutions of these salts it is shown that the total current yields are respectively for lithium sodium and potassium 7556 82*5% and 87%. I n the case of lithium chloride two cases are considered (u) Where the initial concentration of lithium chloride lies on the ascending branch of the conductivity cusve (concentrations below 5N) ; here the fraction of the current carried by the lithium chloride diminishes due to the presence of lithium hydroxide and to the reduction of the salt concentration.( b ) Where the initial con- centration lies on the descending branch of the conductivity curve (concentrated solutions) ; here the yield is diminished by the lithium hydroxide present but it is increased by the fact that the reduc- tion of the lithium chloride concentration brings with it an improve- ment of the conductivity of the salt The Transport Number of the Ions of Cadmium Iodide. GEORGES HEYM (Ann. Physique 1919 [ix] 12 443-454).-From a series of measurements i t is shown that the transport number of iodine ions varies from 0.55 to 1.0 for solutions of cadmium iodide in which the concentration varies from 0-007 to 0.07 gram of iodine per litre.W. G . Electrochemistry of Uranium and the Single Potentials of Some Oxides of Uranium. CHESTER A. PIERL~ (J. Physical (:hem. 1919 23 517-553).-The electrolysis of uranium com- pounds in various solvents and under many conditions has been investigated. It is shown that in aqueous solutions with low current density uranyl salts deposit in the first place hydrated uranic oxide U03,H,0 which is changed as the electrolysis pro- ceeds to a black oxide of varying composition. With higher current density uranyl sulphate is reduced to uranous sulphate but in the presence of free acid the deposit obtained is small in amount and poorly adherent although metallic in appearance. I n neutral or alkaline solutions the deposit formed is a mixture of black and yellow oxides.The use of a porous cup diaphragm does not change the character of the deposits. The deposit obtained when alkaline uranyl tartrate or citrate solutions art? electrdysed is an oxide much richer in uranium than that deposited from solutions acidified with t.artaric or citric acid. The con- ductivity of non-aqueous solutions of uranyl salts is a function of the water present and the deposite formed are oxides contaminated with organic matter Anhydrous pyridine dissolves anhydrous uranium tetrachloride to form conducting solutions ; these on electrolysis deposit a compound containing uranium and pyridine on the cathode.. Solutions of uranium tetrachloride in acetone do not yield metallic uranium on electrolysis; the solution is a good conductor of electricity. The deposit obtained replaces mercury from mercurous sulphate.Uranium tetrachloride reacts with anhydrous acetone forming PP-dichloropropane. During electro- J. F. s.GENERAL AND PHYSICAL CHEMISTRY. ii. 81 lysis hydrogen is evolved. Solutions of potassium uranyl fluoride whether acid alkaline or neutral form a deposit containing fluorine; in acid solution the deposit is UF4,6H,O; neutral and alkaline solutions give a deposit containing uranium tetrafluoride and uranium oxide. Deposits obtained from neutral solutions of potassium uranyl cyanide consist of pure potassium uranate. When acidified with hydrocyanic acid the deposit is the yellow hydrated oxide contaminated with a little of the black oxide.The single potentials of the metal and the oxides have been measured by pasting the finely powdered material on a platinum electrode with gelatin. The followin potentials of the more stable oxides have been obtained U,OjUO,(NO,) 14.3 grams per litre// = 0.776 volt; UO,,H,O I UO,(NO,),[I = -0.860; black oxide from aqueous uranyl salts 1 U02(N0,) I/ = - 0'6872 volt ; uranium 91.49% I UO2(NO3),I/ = - 0.093 volt. Uranous oxide UO giv? a single potential identical with that obtained for the green oxide U,O,. The black deposit formed when uranium salts are electro- lysed is not U,08,2H,0 as stated by Smith (Amer. Chem. J . 1879 1 329) but a compound U,0,,,2H20 and it has a different potential to that of U,O,. Johan Gadolin's Electrochemical Theory its Origin and Development.H. G. SODERBAUM (Medd. K. Vetenskapsakad. Nobel- I n s t . 1919 5 No. 9 l-l4).-Historical. Diamagnetic Phenomenon in Luminous Nitrogen and the Magnetic Behaviour of its Band Spectrum. W. STEUBINQ (Physikal. Zeitsch. 1919 20 512-519).-The intensity changes of the nitrogen bands in a magnetic field have been examined with the magnet in various positions. It is found that if a flat bulb 33 mm. in diameter is blown in the middle of the tube and the tube filled as for an ordinary spectrum observation the light passes across the bulb in the ordinary way except that the positive column is slightly broadened. When the field is made active the middle of the bulb is filled with a blue luminous sheath which extenas up to the walls and is at right angles to the lines of force of the field.This sheath has an identical spectrum with the negative luminescence and is probably to be accounted for by the diamagnetic molecules setting themselves a t right angles to the magnetic lines. Magnetic Properties of some Rare Earth Oxides at Low Temperatures. E. H. WILLIANS (Chem. News 1919 119 287-288) .-The magnetic susceptibility of the oxides of dyspros- ium erbium gadolinium samarium neodymium lanthanum and yttrium has been determined a t a series of temperatures from 2OC to - 140O. The following values are given Dysprosium oxide 20° 384'2; -120° 430.2; -140' 490.0. Erbium oxide 20° 188.6; - 140° 402.8. Gadolinium oxide 20° 129.7; Oo 138.2; -40° J. F. S. T. S. P. J. F. S. X x lo6 233.3'; O' 250'0; -40° 291'3'; -80° 347'4; -loo' O' 201.7; -40° 234.8; -goo 282'3; -looo 314'8; -120° 355'0; 160.7; -80° 194'3; -looo 217.0; -120' 244'6; - 140° 279'0.ii.82 ABSTRACTS OF CHEMICAL PAPERS. I n all cases the oxides were purer than 99.5%. I n the case of samarium oxide the susceptibility a t -140° was about 10% larger than at 20°. Yttrium oxide increases in susceptibility with decrease in temperature but very slightly and since the susceptibility is less than 1 x 10-6 the experimental error is relatively large. It is shown that the product of the susceptibility and the absolute temperature is not constant but decreases with falling temperature to a slight extent. J. F. S. The Paramagnetism of Solid Salts and the Theory of the Magneton. B. CABRERA (Anal. Fis. Quim. 1918 16 436-449).-A mathematical discussion of the Curie-Langevin law when the mutual actions of the paramagnetic atoms are no longer negligible.W. S. M. WALTER P. WHITE and LEASON H. ADAMS (Physical R e g . 1919 14 .4448).-By making the heating coil of an electric furnace one arm of a Wheatstone bridge and combining this wit,h a galvanometer regulator thus keep- ing the resistance of the coil constant the temperature of electric furnaces may be kept constant. This device is effective regardless of variations in the current supply and requires no attention particu- larly in the case of furnaces which are not directly influenced by the temperature of the room or where the surrounding air is kept constant. The arrangement operates as follows Changes in the temperature of the furnace and consequently in the resistance of the heating coil operate a boom which either hits or misses a contact-maker which controls a suitable relay.This relay operates a larger magnet which controls the main current. The power available in this regulator is verv large; nothing has to be inserted into the furnace cavity and the lag is practically non-existent. The regulator is often almost a t its best under conditions most unfavourable t o other regulators. Using this regulator the authors have kept a small furnace constant to within 0’lc for hours a t temperatures from 500° to 1400O. An Analysis of the Radiation Emitted in Gaseous Explosions. W. T. DAVID (Phil. Mag. 1920 vi 39 84-95)- I n explosions of coal-gas and air and of hydrogen and air the ratio of the energy in the 2.8 p radiation emitted to that in the radiation of longer wavelength decreases as the temperature decreases. In the neighbourhood of 1200O abs.the 2.8 p radiation decreases very rapidly with the temperature and is negligible at 1000° abs. Radia- tion of longer wavelength is emitted after the temperature has fallen to 900° abs. but a t this temperature the emission is small. The ratio of the energies in the 2.8 p and the 4.4 p radiation in coal- gas and air mixtures appears to depend on the composition of the mixture and the temperature. The loss of heat by radiation expressed as a percentage of the heat of combustion of hydrogen and air mixtures between the limits of composition of 10 and 25.4% of combustible gas decreases very rapidly as the latter increases.Furnace Temperature Regulator. J. F. S.GENERAL AND PHYSICAL CHEMISTRY. ii. 83 The variation for mixtures of coal-gas and air between 9.8 and 15% is small. The author attempts a theoretical explanation of these results on the following lines. The intra-molecular energy acquired on combustion by the freshly-formed molecules of carbon dioxide and water is not equally partitioned over the various internal degrees of freedom of the molecules. When the combustion is gentle the intra-molecular energy is concentrated in the rotational degrees of freedom and in such very low frequency vibrations as the mole- cules may be capable of executing. As the combustion becomes more violent the higher frequency vibrations share in this energy and it is possible that during combustion of extreme violenoe equi- partitioning of energy amongst all the internal degrees of freedom of the molecules may be approached momentarily.This is believed to be capable of explaining many phenomena of explosive combus- tion such as the pre-pressure period. Isothermals of Monatomic Substances and their Binary Mixtures. XX. Isothermals of Neon from 20' to - 217O. C. A. CROMMELIN J. PALACIOS MARTINEZ and H. KAMMERLINGH ONNEE (PTOC. R. Akad. Wetensch. Amsterdam 1919 22 108-118. Compare A. 1917 ii 407; 1918 ii 9).-The isothermals of neon have been determined over the range 20° to - 2 1 7 O up to a pressure of 90 atms. by the method previously described. From the results of the experiments the authors have calculated the virial-coefficients from the equation of state.It is shown that the pv values obtained in the present work agree in a very satisfactory manner with the older measurements. Only in the isothermal -217'52O is any marked divergence visible and here the divergence does not exceed 0'5%) whilst for the isothermal -200'08O they do not reach 0.1%. J. F. S. A New Improvement of the Equation of State of Fluids. E. ARIBS (Compt. rend. 1919 169 1140-1143).-A mathemati- cal disoussion of the subject. Equation of Condition. FRED. G . EDWARDS (Chem. News 1920 120 4-5).-Using Nernst's value in the equation for the mean molecular heat of gases Cv=a+ b t it is shown that these linear equations are chords to the curve mz= k log T where m= 5 . 9 5 1 ~ or 4 - (2~12.975) below or above y=2.975 from which is obtained the general equation m2= kllog T = 1 / v log T and hence pv = mZT mz being a constant for monatomic gases.Corrected van der Waals's Equation of Condition for the Quasi-diminution of the Molecule. E. A. HOLM (Medd. R. Vetenskapsakad. Nobel-Znst. 1919 5 No. 27 1-33).-1n the cor- rected van der Waals's equation an infinite series of b l v appears as the correction factor of the volume. This has been inserted by Boltzmann i n an approximated form as 1 - b / v + 0*375b2/va- 0'0369bSlvS. This cannot be true for very small volumes. The equation has been tested on Amagat's oxygen isotherms and it is J. R. P. W. G. W. G.ii. 84 ABSTRACTS OF CHEMICAL TAPERS. found to be strictly applicable at pressures 260 300 and 450 atm. and a t temperatures Oo 15.63O 99.50° and 1 9 9 ' 5 O .The negative divergence found for very high pressures is due entirely to the mathematical incompleteness of the formula J. F. S. Determination of Chemical Constants. ALFRED C. EGERTON (Phil. B a g . 1920 [vi] 39 1-20).-The author emphasises the fact t h a t the usual formula for the calculation of chemical con- stants from vapour pressures due to Nernst cannot give results having any theoretical significance because the assumptions as to the specific heats a t low temperatures which are contained i n it have been shown to be incorrect by recent experiments. H e there- fore modifies the formula by substituting for these assumptions the more exact expressions for the specific heats of solids a t low tem- peratures and assumes t h a t the atomic heats of gases remain con- stant and equal t o 5 1 2 .R a t the lowest temperatures. Thevaluesof the chemical constants calculated by the new formula agree within the limits of experimental error with those given by the formula - C',= C - 1.5 log M where C is a universal constant and M is the atomic weight. The values of C obtained from the vapour-pressure formula are given in the second column below; those from the above formula in the third column C from vap. press. Mercury ............ 1.820+_0.03:! 1.845 Cadmium ... 1.65 k0.31 1.468 Zinc . . . . . . . 1.23 f 0.26 1.115 The latent heats of vaporisation are calculated from an expression previously used (Phd. Mag. 1917 [vi] 33 193) and found to agree with the experimental values as well as those calculated by the equation X = T"8.5 log T due to Nernst.The value of Stefan's constant u is calculated and found t o be5.27. erg. cm.-2 deg.-4 which agrees with the value adopted by Planck but is distinctly lower than the more recently determined values. Significance of the Chemical Constant and its Relation to the Behaviour of Gases at Low Temperatures. F. A. LINDEMANN (Phil. ,&fag. 1920 [vi] 39 21-25).-It is shown t h a t the chemica.1 constant has the dimensions of the logarithm of a pressure if the atomic heat of a monatomic gas becomes zero at the absolute zero. I n this case it should be of the form X + 312 . log A + 5 / 2 . log 8 where 8 is a characteristic constant of the substance. If the atomic heat of a monatomic gas remains 5 / 2 . R down to the absolute zero the chemical constant has the dimensions of a pres- sure divided by a temperature to the power 512 and is of the form X + 3/2 .log A . Experimental determinations show that the latter form is true within the limits of error. It follows either that 6 is very nearly equal to lo for all substances which seems improbable or t h a t the atomic heat remains constant down t o the lowest tem- peratures. It is further shown that the chemical constant may be eliminated and the vapour pressure expressed i n terms of the pressure of full radiation. It is therefore suggested that the C from formula. The value of C is found to be -1.622. J. R. P.GENERAL AND PHYSICAL CHEMISTRY. ii. 85 chemical constant may express the interaction of matter and full radiation rather than requiring that a gas can assume only a finite number of microphases from the point of view of statistical mechanics a t a given temperature pressure and volume.If the value of the chemical constant could as suggested be derived from the radiation pressure the quantum assumption would be avoided iii the case of gases although it would be necessary for t.he deduction of the law of full radiation. Latent Heat and Surface Energy. 11. D. L. HAMMICK (Phil. Mag. 1920 [vil 39 32-46. Compare A. 1919 ii 389).- On the assumption that van der Waals’s constant a varies with the temperature a relation is derived between the surface energy p the molecular volume I’ and a namely a,=6pV/d where d is the molecular diameter. This is valid a t low temperatures only. By assuming that aT diminishes linearly with the temperature to the critical value a,.latent heats are calculated by Bakker’s formula A=aT(l/ul-l/u2) for several liquids.The results are in good agreement with experimental values. The ratio a T / a c is found to be the same for many liquids a t the boiling point and equal to 1.4. This leads to the value of Trouton’s constant. The empirical rela- tionship between latent heat and surface energy due to Walden and the Eotvos-Ramsay law can also be deduced. Heats of Fusion Velocities of Crystallisation and Chemical Affinities in Crystals. M. PADOA (Atti R. kccad. Lincei 1919 [v] 28 ii 239-243. Compare A. 1919 ii 51 96). -From the considerations previously developed the conclusion is drawn that the affinity acting in the process of crystallisation should be expressed by or a t least included in the heat of fusion of the compound so that under similar conditions as t o molecular magni- tude and structure those compounds exhibiting the greatest veloci- ties of crystallisation should also have the highest heats of fusion.The melting points heate of fusion and velocities of crystallisa- tion are tabulated for a number of pairs of isomorphous organic compounds such as naphthalene and dihydronaphthalene benzene and cyclohexane etc. I n each pair the greater heat of fusion corresponds with the greater velocity of crystallisation character- istic of the compound containing double linkings. Further un- saturated compounds in general melt a t higher temperatures than the corresponding saturated compounds this indicating the greater stability of the crystals of the former.As regards heats of fusion the values f o r different series of compounds cannot be compared the value for the saturated ethyl succinate for instance exceeding that for benzene; thus the heat of fusion may be the resultant of various thermal effects and not merely the effect of the affinity inherent to the union of the molecules in the crystal in the same way as the heat of solution represents the algebraic sum of the various heats of ionisation hydration etc. With a compound containing a triple linking such as tolane the velocity of crystallisation is less than that for the corresponding J. R. P. J. R . P.ii. 86 ABSTRAOTS OF CHEMICAL PAPERS. isomorphous compound with a double linking (stilbene) and approaches that for the corresponding compound with a single linking (dibenzyl).The parallelism between velocity of crystal- lisation and heat of fusion is maintained also in this case; the melt- ing points of compounds with triple linkings are likewise lower than those of the compounds with double linkings. The high velocities of crystallisation shown by compounds with double linkings are explainable on the assumption that change of form on crystallisation is unnecessary with these compounds which in the liquid state are wholly of the fumaric or wholly of the maleio type and with the help of the latent valencies crystallise with great rapidity; on the other hand the compounds with single or triple linkings undergo in part a t least a preliminary transposition which results in retardation of the crystallisation. As an instance of the influence of the molecular configuration it may be noted that the velocity of crystallisation of dibenzyl with which equil- ibrium between the cis- and trans-forms is possible in solution is 580 mm.per minute whereas that of dihydrophenanthrene which differs from dibenzyl only in the closure of the third ring and with which no equilibrium between isomeric forms is possible is 1200 mm. per minute. It may be however that the results obtained with compounds containing the three different linkings are to be explained by the assumption that the latent valencies of the triple linking exert no action in the formation of crystals. Thomsen’s thermochemical calculations (“Thermochemische Untersuchunpen.” 1906.310) i \ i I 3cm 4 show that the thermal value of :simple linking in . -3 .- the lower members of the paraffin seriea is 14.71 cal. whereas that of the double linking in the correspond- ing olefines is 13.27 cal. and that of the triple linking in acetylene etc. approaches zero. W c m . T. H. P. Apparatus for Determining the Melting Point of Very Hygroscopic Substances. H. J. BACKER (Chem. W e e k h l a d 1919 16 1564-1565).- The apparatus consists of a narrow thin-walled glass tube into which the material under examination is placed the tube being then drawn out and sealed. It communicates by means of a small curved latera? branch with a wider tube in which is placed about 2 C.C. of phosphoric oxide after which this tube is drawn out into a capillary exhausted by means of a water-pump and sealed The material is thus con- tained in a vacuum desiccator during the determin- ation of its melting point.w. J. w. Freezing-point Lowerings in Mixtures of Two Electro- lytes. K. G. DERNBY (Medd. K. Vetemkapsakad. Nobel-Inst. 1918 3 NO. 18 l-lO).-The depression of the freezing point has been determined for aqueous solutions of mixtures of two electrolytes. The following pairs were examined bydro.chloric acid and the,GENERAL AND PHYSICAL CHEMISTRY. ii. 87 chlorides of sodium potassium and magnesium respectively potassium and magnesium chloride nitric acid with potassium and magnesium nitrates respectively. The concentrations examined varied between ON and 0 * 8 N . It is shown that the freezing-point lowerings of mixtures of electrolytes with a common negative ion are always greater than the sum of the individual lowerings.For mixtures of binary electrolytes such as KCl,HCl NaCI,HCl KNO,,HNO the lowering of the freezing point is approximately proportional to the concentration of the salt and of the acid. For mixtures of a ternary electrolyte and a binary electrolyte such as RIgCl,,HCl MgCI,,KCl and Mg(NO&HNO the lowering of the freezing point increases faster than the concentration. Mixtures of magnesium chloride and hydrochloric acid lower the freezing point more than mixtures of potassium chloride and magnesium chloride of the same concentration. J. F. S. CalcuIation of the Neutral Salt Action from the Depres- sion of the Freezing Point of Aqueous Solutions. SVANTE ARRRENIUS and ERIK ANDERSSON (Medd.R. Vetenskapsakad. Nobel-lnst. 1918 3 No. 25 1-9).-A theoretical paper in which on the basis of the Arrhenius hypothesis of the mechanism of neutral salt action an attempt is made to calculate the neutral salt action from freezing-point depressions. The osmotic pressure of a solution is strongly influenced by other substances particularly salts; this is also true of the osmotic pressure of hydrogen ions. Since the velocity of reaction is proportional to the osmotic pressure of the surrounding substance (sucrose or ethyl acetate) and further the osmotic pressure of the catalyst (hydrogen ions) increases pro- portionally the neutral salt action can be calculated as scan as the corresponding changes of the two osmotic pressures are known.These for the case under investigation are known from the freez- ing-point measurements of Dernby (preceding abstract) and from the hydrogen-ion activity determinations of Harned (A. 1916 ii 8). The calculation shows that the method is one capable of furnishing the desired result Simplification of the Inverse-rate Method for Thermal Analysis. P. D. MERICA (B~11. Bureau Standards 1919 No. 336 101-104).-1n plotting and recording cooling curves the author recommends the following method using a thermocouple a direct- reading potentiometer and galvanometer and two stop-watches. The watches are mounted in a single frame and held in one hand ; the potentiometer is set a t the desired point. When the time- temperature readings are being made the stem of both watches is pressed a t the moment the galvanometer reaches the zero thus stopping one watch and so recording the time interval and start- ing the other watch on the next interval which is recorded in the same way.This method saves the time necessary in plotting and reading chronograph records and does away with the use of ex- pensive chronographs. Specimen curves f o r the cooling of iron made by this method are given in the paper. J. F. S. J. F. S.ii. 88 ABSTRACTS OF CHEMICAL PAPERS. Exact Formula for the Saturation Tension of Water Vapour between 0' and 50'. PAUL SCHREIBER (Physikal. Zeitsch. 1919 20 521-523).-The author gives the following formulze for calculating the saturation tension of water vapour a t temperatures between Oo and 50° log s= log s1 + log f ( T ) in which logsl=p+p logT and logf(T) is a correcting factor s is the corrected saturation tension.The values calculated by this equa- tion are practically identical with the values given in the inter- national meteorological tables. The values log sl= - 7.0814 + 17.8 log (10-22')) logf(T) =0*0115 -0*0000494(2"-298)2 and are used in the calculations. F. P. SOEBEL (Science 1919 50 49-50).-Assuming that at the b. p. the energy of vibration of the individual molecules of a liquid and of its vapour must be equal the author deduces the equation T,=mp,v,/1.49 for a pure liquid,.where m is the molecular weight and p and v the pressure and the volume of the vapour a t the absolute b. p. T,. For ordinary liquids containing impurities the equat.ion becomes T,= (p,v,-C)m/1~49 where C is a constant characteristic of each liquid.I n the case of water (m = 18 ; C = 8.7) the calculated values of T a t 273O 313O and 473O (abs.) are 270° 313*3O and 473.5O respectively. Similar agreement is found in the case of other liquids in which association does not occur. Vapour Pressure and Free Energies of the Hydrogen Haloids in Aqueous Solution. The Free Energy of Formation of Hydrogen Chloride. STUART J. BATES and H. DARWIN KIRSCHMAN (1. Amer. Chem. Soc. 1919 41 1991-2001). -Determinations have been made of the vapour pressures of hydrogen chloride hydrogen bromide and hydrogen iodide above their aqueous solutions between the concentrations 3.2 and l O . O M 5.8 and ll*ON and 6.0 and 9.7N respectively a t 25O and of hydrogen chloride between 5.5 and 9.2N a t 30°. By the method employed which consisted in determining the hydrogen haloid contained in a given quantity of air or nitrogen in equilibrium with its solution and comparing this with the amount of aqueous vapour which the same air contained when in equilibrium with pure water a t the same temperature partial pressures as small as 0.001 mm.were determined with an accuracy of a few per cent. The vapour- pressure measurements of hydrochloric acid solutions between 3'2N and 7.15N are in good agreement with the E.M.F. data for hydro- chloric acid concentration cells. The free energy of formation of hydrogen chloride a t 25O is -22,700 cal. The free energies of formation of the halogen acids a t various concentrations 0'1-1 1.0 mols.per litre in aqueous solution are given in a table in the paper. Conatant Temperature Still-head for Light Oil Frac- tionation. FREDERICK &I. WASBBURN (J. Id. Eng. Chem. 1920 12 73-77).-The apparatus described consists of two essential log S = - 7.0699 + 17.8 log (10-2T) - 0*0000494(T -298)' J. F. S. Boiling Point of Liquids. CHEMICAL ABSTRACTS. J. F. S.GENERAL AND PHYSICAL CHEMISTRY. ii. 8 parts namely a Hempel column and a constant temperature still- head of the type suggested by F. A. Brown (T. 1880 37 49). This still-head is a spiral of about 6 inches diameter made from 12 feet of $ inch iron tube; it is surrounded by an oil-bath which is provided with a stirrer and maintained at the required temperature by a coil of resistance wire thernio-regulator relay etc.The lower end of the spiral is connected with the side-tube of the Hempel column whilst the upper end is fitted with a thermometer pocket and a side-tube leading t o an ordinary condenser. Heat of Formation Calculated from the Wave-length of Absorption Bands. A. L. BERNOUILLI (Helw. Chim. Acta 1919 2 720-728).-The author has deduced an expression whereby from the absorption bands corresponding with characteristic ultra-violet electron vibrations the heat of formation of a compound from its elements may be calculated. This expression for a binary com- pound - - - has - Q = 0~01128[(~~@l/avl~ - / c % / ~ w ~ $ ) - d/O'/(a+@-6)v'$] i n which Q is the heat of formation q w2 and d the atomic volumes of the constituent elements and the molecular volume of the compound respectively; @ a and a' are the melt ing points i n absolute degrees of the elements and the compound respectively a and j3 are the electron numbers or valencies of the elements and 6 is the number of charges given up i n the formation of the molecule.This formula is tested in the case of a number of binary compounds and the results compared with the experimental values. The two sets of results are remarkablv close for example. W. P. S. the - form A carbon dioxide calc. 108.3 obs. 106.0 ; silverdchloride calc. 29.05 obs. 29.0. J. F. S. Heat of Reaction of Ammonia Oxidation. GUY B. TAYLOR (1. Znd. Eng. Chem. 1919 11 1121-1123).-The temperature most favourable to the catalytic oxidation of ammonia by means of air is 800O. In order to determine the amount of external energy required t o maintain the catalyst a t the optimum temperature a formula has been based on the equations (1) 4NH3+5O2=4NO+ 6H20+ 214200 cal.( 2 ) 4NH + 30 = 2N + 6H,O + 300600 cal. The temperature rise is expressed by the formula t = Q/C where Q represents the heat of reaction i n calories and C the specific heat of the products of the reaction. From Oo to 800° water-vapour is the only gaseous product with an appreciable temperature-coeffi- cient and this may be taken as 8.34. I n the following formula t0=(75150x- 21600y)/(7~~08+3*41a-O~25y+ 8.34VIB- V ) V re- presents the partial pressure of water-vapour B the total pressure of the air-ammonia-water vapour mixture 5 the molecular fraction of ammonia i n the mixture and y the molecular fraction of nitric oxide produced in the oxidation.For maintaining the catalyst a t the right temperature preheating the mixture electric heating or enriching the current of ammonia and air with oxygen have been shown to give equally satisfactory results. C. A. M.ii. 90 ABSTRACTS OR CHEMICAL PAPERS. Critical Densities of Hydrogen Helium and Neon. J. J. VAN LAAR (Chem. Weekblad 1919 16 1557-1564).-1n thecases oi hydrogen and helium the extrapolated values for Do obtained from the curve B(Dl+D2)=f(T) are found to be too high. Thus the figure 0*0310 so obtained for hydrogen would correspond to y =0.46 which is an impossible value. The author calculates that for hydro- gen D,=0.0287 and for helium D,=0*0598 instead of 0.066 as given by the curve. I n the case of neon there is agreement between the extrapolated value and the calculated figure U being 0.456.The ‘‘ Density Numbers ” of Groshans. W. P. JORISSEN (Chem. Weekblad 1917 14 1066-1071).-The volume in C.C. of 1 gram of a vapocised substaiicc a t tho boiling point is given by the expression 82T / M where llf is the molecular weight. Elimination of Tb,p. between this expression and the boiling point formula of Groshans Tbp = 27*8iMdi/n gives the vapour volume in C.C. of 1 gram 2280dxln. x is a constant for the class of substances con- sidered and n is the sum of the density numbers of the elements involved (Ann. Phys. Chcm. 1849 78 116). For the elements carbon hydrogen and oxygen the density numbers are unity and n is therefore the number of atoms in the molecule.For other elements n is greater than unity. For unassociated liquids the expansion in the transition from liquid to vapour is 570&. By comparing this formula with the expansion determined experimen- tally by Masson (A 1891 379) for methyl ethyl propyl phenyl butyl and amyl chlorides x is determined for each and the density number for chlorine is determined from the boiling-point formula. The values found range from 3’40 to 4.44. The value given by Groshans is 4. Determination of Avogadro’s Normal Volume V and of the Atomic Weights of Hydrogen Helium and Argon. J. J. VAN LAAR (Chena. Veelcblad 1919 16 1243-125O).-A con- tinuation of it previous communication (A. 1919 ii 461). The most probable value of VIA is considered to be 224153 C.C. The atomic weights of hydrogen helium and argon are stated to be 1.007697 (= 1’00770) 3.9998 (=4’000) and 39.95 respectively.W. J. W. W. S. M. W. J. W. Molecular Attraction. 111. The Characteristic Equation. K. K. JARVINEN (Ann. Acad. Sci. Fennicae 1919 [ A ] 12 Reprint 44 pp.).-A continuation of the theoretical discussion on molecular attraction (compare A. 1913 ii 293; A. 1915 ii 251). The internal prmsure pa is calculated by the equation p = R TI V . f -pa on the basis of the law of molecular attraction F=lem2/r5. It is found that pa=a/vi for monatomic substances and pa=a/ { v + ( v ~ - 0.242b*)5} for polyatomic substances where a and b are the cbn- stants of van der Waals’s equation. It is thus much smaller than that calculated from the latter equation. The critical pressure p h = R T / V .f is also calculated and thence a table of values of fGENERAL AND PHYSICAL CHEMISTRY. ii. 91 deduced which may be used to find the deviations from the ideal state. Values of f are also calculated from the equations f = p - p a / RT . v and f = d p / d t . v / R the latter obtained by differentiation of the characteristic equation. These agree approximately with the theoretical values. The differences are taken to mean that the theory is yet incomplete. It is also found that b decreases with temperature but this need iiot in reality be the case. The pressure the critical data and the values of vk/bo RT/pvk d p l d t . v / R and d p / d t . T / p may be obtained with fair approximation. Only approximate accuracy is claimed. Effects of Acids and Bases on the Surface Energy Relations of PP‘-Dichloroethyl Sulphide (Mustard Gas).WILLIAM D. HARKINS and D. T. EWING ( J . Amer. Chem. SOC. 1919 41 1977-1980).-The surface tension between &3’-dichloro- ethyl sulphide and a number of liquids has been determined with the object of finding a suitable emulsifying agent for the prepara- tion of aqueous emulsions of this substance. The following values of the surface tension in dynes per cm. have been found between &3’-dichloroethyl sulphide and the liquids named water 28.36 ; O.1N-hydrochloric acid 28.90 ; O’lN-sodium hydroxide 12-78 ; O’liV-sodium carbonate 18.82; 1% solution of turkey-red oil 14.47 ; 1% solution of turkey-red oil in O‘lN-sodium carbonate 8.35; ls’o Twitchell’s solution 12.32 ; 1% Twitchell’s solution in O’lN-sodium carbonate 12.89; 1% maize oil solution 12.94; and 1% maize oil in O‘IN-sodium carbonate 10.91.The surface tension of several organic liquids has also been measured aa-diphenylpropane 20° 37.15 25O 36.64; aa-diphenylethane 20° 37.67 25O 37.20; diphenylmethane 20° 37.56 ; ditolylmethane 20° 35.51 25O 34.80; propylbenzene ZOO 32.22 25O 31.30. All determinations were made by the drop-weight method. J. R. P. J. F. S. Viscosity of Pure Liquids. SVANTE ARRHENIUS (Xedd. K. Vetenskapsakad. Nobel-lnst. 1918 3 No. 20 140).-A theoreti- cal paper in which a large volume of work on the viscosity of liquids is discussed and correlated. It is shown that the ratio q b x 105 d F i s approximately constant for non-associated organic liquids. The symbols have the significance qb is the viscosity of a liquid a t the boiling point and s is the density and the constant varies between 230 and 320.The constant is not obtained in the case of a few liquids which are characterised by the fact that the expression Kl = P ( d log 7 id) / d t does nof show a minimum below the boiling point. These liquids are ethylene propylene and iso- butylene bromides benzene and carbon tetrachloride. The presence of negative atoms such as the halogens sulphur or oxygen increases the value of the ratio q b .\/; The iduence of pressure 011 the viscosity is nearly represented by a linear equation log qp= logqo+Z(p-po) where qo is the viscosity a t the external pressure zero (practically atmospheric pressure) p is the total pressure (external and internal) calculated according t o van der Waals’sii.92 ABSTRACTS OF CHEMICAL PAPERS. theory and p the internal pressure a t zcro external pressure. The influence of temperature on viscosity may for non-associated liquids be expressed by the formula dlog q . d / d t = R / T 2 . K is nearly proportional t o the absolute boiling point Tb so t h a t K Tb if ordinary logarithms are used for calculatiiig Kl does not change for normal organic liquids between greater limits than 1-1.2. Benzene and the liquids named above are exceptions. For associated liquids the ratio R Th possesses higher values between 1‘25 and 4.32. There is a pronounced parallelism between the values of the ratios q b d/sand R Tb. I n an homologous series li’ Tb gener- ally increases with the boiling point.There is a great analogy between the effect of temperature on the vapour pressure and on the product of the viscosity and the specific volume. J. F. S. Investigations concerning the Viscosity of Binary Liquid Mixtures. HANS EGINLR (Medd. K. Vetenskapsakad. Nobel-Inst. 1918 3 No. 22 1-13).-A4 theoretical paper in which a large number of viscosity determinations of various authors are collected and examined in connexion with the modified logarithmic formula of Arrhenius log i i = n log q1 + n2 log q2 where and v2 are the viscosities of the components of the mixtures and n and n2 the molecular concentrations. It is shown that this formula represents the variation of the viscosity in binary liquid mixtures more exactly than any other formula.J. F. S. Theoretical Signiflcance of Viscosity Measurements of Colloidal Solutions. SVASTE ARRHENIUS (Medd. K. Vetens- Lapyakad. h T o b e l - l m t . 1918 3 No. 21 1-22).-A theoretical paper i n which a large number of viscosity determinations of colloidal solutions are discussed. It is shown t h a t Einstein’s viscosity formula is fully established by Bancelin’s results (A. 1911 ii 586 1067) as soon as the logarithmic formula is employed. The proposed extension of Einstein’s formula put forward by Smoluchowski is not confirmed by Oden’s measurements on colloidal sulphur (A. 1913 ii 485). Viscosimeter for Measuring Viscosities and Fluiditiee. GEORGES BAUME and HENRI VIGNERON (Ann. Chim. and. 1919 [ii] 1,379-383).-The viscosimeter tube consists of a capillary pro- vided with a bulb at? its upper end and a short length of wide tube a t its lower end; this tube is fixed vertically by means of a cork in a test-tube containing 20 C.C.of the oil under examination the lower end of the tube being immersed i n the oil up t o a mark just below the capillary. A thermometer passes through a T-piece carried by the cork the bulb of the thermometer dipping into the oil. The test-tube is inserted in a boiling bulb provided with a reflux apparatus This boiling bulb may contain ether acetone. benzene or water according t o the temperature a t which the viscosity is t o be determined ; when the required temperature has iogr-iogqp=e+ J. F. S.GENERAL AND PHYSICAL CHEMISTRY. ii. 93 been reached the oil is forced upwards into the viscosimeter tube by a pressure ball attached to a branch of the T-piece; the pressure is then released and the time taken f o r the level of the oil to fall from a mark just above the bulb (on the viscosimeter tube) to one Emulsification by Adsorption at an Oil-Water Interface.S. E. SHEPPARD (J. Physical Chem. 1919 23 634-639).- Emulsions of nitrobenzene in sulphuric acid and hydrochloric acid may be readily prepared by making the acid of the same density as the nitrobenzene. Similar moderately stable emulsions were prepared by saturating the acid (sulphuric) with lead sulphate or calcium sulphate or hydrochloric acid with sodium chloride or lead chloride in both cases the acid being of the same density as the nitrobenzene. It therefore appears that in accordance with Ban- croft’s general theory of peptisation adsorption a t a liquid-liquid interface is capable of effecting emulsification.The systems thus produced on’ ageing pass into a condition approaching Pickering’s emulsions but with a great diminution of the dispersity. just below i t is noted. w. P. s. J. F. S . Nature of Osmotic Pressure MITSUJI KOSAKAI (Proc. SOC. Ezpt. Biol. Med. 1919 16 118-119).-The hnmolytic effects of formaldehyde and carbamide were found to be like that of boric acid the result of osmotic pressure. The rates of diffusion of boric acid formaldehyde and carbamide are 90 sec. 30 sec. and less than 5 sec. respectively. These differences correspond with the differ- ences in the hamolytic action of the three substances and confirm the view that osmotic pressure is not a direct property of a solute but is merely water pressure developed by the process of diffusion.CHEMICAL ABSTRACTS. Osmotic Pressure. 11. The Nature of Osmotic Pressure MITSUJI KOSAKAI ( J . Immunology 1919 4 49-65).-The same degree of osmotic hEmolysis is not produced by identical concentra- tions of boric acid formaldehyde and carbamide or by a corre- sponding lowering in the medium of suspension of the treated corpuscles. As the treating concentration of the three hnmolytic substances is correspondingly diminished the ratio between that concentration and the final concentration in the hnmolytic experi- ment increases disproportionately with the different substances. The osmotic hzemolysis of corpuscles which have been treated with the three hzmolytic substances in the same osmotic concentration is not inhibited by identical concentrations of sodium chloride or of the hnmolytic substances themselves. All these facts contradict the assumption that osmotic pressure is exerted directly by the solute.Osmotic pressure is not a direct property of a solute but is solely the pressure exerted by water which has passed by the unexplained process of diffusion through a semipermeable mem- brane to the side of the higher osmotic concentration. CHEMICAL ABSTRACTS.ii. 94 ABSTRACTS OF CHEMICAL PAPERS. Osmotic Pressure of an Electrolyte. OSKAR KLEIN (Medd. K Vetenskapsakad. Nobel-lnst. 1919 5 No. 6 1-9).-A mathe- matical paper in which an expression is deduced showing the con- nexion between osmotic pressure concentration temperature and dielectric constant.The reasoning is based on thermodynamical and mechanical (kinetic) principles and is simpler than that used by Milner (A 1913 ii 481) in a similar problem. T. S. P. The Diffusion of Electrolytes into Jellies. 11. The Dependence of the Diffusion on the Mobility of the Ions and the Hydration and Polymerisation of the Molecules. OTTO VON FURTH and FRANZ BUBANOVIO (Biochem. Zeitsch. 1918 92 139-170. Compare A. 1919 ii 13).-Diffusion in jellies differs in most cases from free diffusion in aqueous solution and is dependent on the character of the jelly. The velocity with which acids bases and polymerised salts penetrate jellies is smaller than would be expected from the mobility of their ions. Weakly hydrated salts show normal diffusion (diffusion similar to that in aqueous solution) in jellies.St,rongly hydrated salts on the other hand contrary to their behaviour in aqueous solution diffuse relatively faster than in the previous case so that their diffusion velocity approximates to the theoretical value obtained from the mobility of the ions. s. s. z. Influence of the Concentration of Electrolytes on the Electrification and the Rate of Diffusion of Water through Collodion Membranes. JACQUES LOEB (2. Gem Physiol. 1919 20 173-199).-When an aqueous solution is separated from pure water by a collodion membrane the initial rate of diffusion of water into the solution is influenced in an entirely different way by solutions of electrolytes and of non-electrolytes.The latter influence the rate of diffusion in direct proportion to their concen- tration and this effect is termed the gas-pressure effect. Solutions of electrolytes show the gas-pressure effect also but. it commences a t a somewhat higher concentration than in the previous case. If the concentration of the electrolvte is below that a t which the gas- pressure effect is observed the solutions have a specific influence on the initial rate of diffusion which is not found in the case of the solutions of non-electrolytes and is due to the diffusion of the water in an electrified condition the sign of the charge depend- ing on the nature of the electrolyte in solution according to the theory which has been advanced by the author (A. 1919 ii 497). I n these lower concentrations the curves representing the influence of the concentration of the electrolyte on the initial rate of diffusion of water into the solution show that within a range of concentra- tions between MI256 and MI16 or more (according to the nature of the electrolyte) the reverse of what should be expected on the basis of van’t Hoff’s law is noticed namely that t.he attraction of a solution of an electrolyte for water diminishes with an increase in concentration Whilst no definite assumption concerning theGENERAL AND PHYSICAL CHEMISTRY.ii. 95 origin of the electrification of water and the mechanism by which the ions influonce the rate of diffusion of water particles through collodion membranes is made it is suggested that in the lowest concentrations attraction of the electrified water particles by the ions with the opposite charge prevails over the repulsion of the water particles by ions with the same sign of charge whilst beyond a certain critical concentration the repelling action of the ion with the same charge as that of the water particles on the latter increases more rapidly with increasing concentration of the solute than the attractive action of the ion with the opposite charge.It is shown that negative osmosis is due to the repulsion of the electrified particles of water by the iun with the same charge as that borne by the water. J. C. D. The Effect of Strain on Solubility. J. C. HOSTETTER (Science 1919 50 25) .-It is possible that fluctuating tempera- ture and perhaps some indirect effects brought about by pressure may account for the solidification of crystals compressed in contact with their solution by loosely fitting pistons as found by James Thomson Le Chatelier and Spring without the necessity of postu- lating large increases in solubility due to non-uniform pressure.I n preliminary experimenta individual crystals were subjected to stress a t constant temperature by direct loading and the effect on the concentration of the surrounding solution was studied by measuring the electrical conductivity. No change in concentration was found. The test was sufficiently sensitive to indicate that the effect of non-uniform pressure is much less than that produced by the same pressure acting uniformly. However in another series of experiments in which an unloaded crystal was placed alongside a loaded crystal the former grew at the expense of the latter show- ilig that a very slight increase of solubility was produced by the stress.The method of loading the crystals has a large influence on the effects found thus indicating the importance of the stress distribution. The experiments of Becker and Day on the linear force of growing crystals are cited as indicating the stability of a crystal in its solution even when subjected to pressure. I n their experiments loaded crystals were found to lift the load during growth although the pressures on the supporting edges of the crystals were finally of the order of magnitude of the crushing strength of the crystal. The evidence so far obtained indicates that the effect of strain on solubility is a second-order effect.CHEMICAL ABSTRACWS. Influence of Electrolytes on Solubility. EBBE LINDE (Arkiw. Kern. Min. Geol. 1917 6 No. 20 1-17).-The solubility of ethyl ether and ethyl acetoacetate has been determined in water and in solutions of certain electrolytes. In the case of ethyl ether it is found that 7.88 grams dissolve in 100 C.C. of water a t 1 8 O . The influence of mixtures of two electrolytes on the solubility of ether in water is determined for the pairs of electrolytes sodiumii. 96 ABSTRACTS OB CHEMICAL PAPERS sulphatesulphuric acid sodium sulphate-sodium hydroxide and sodium chloride-sodium acetate. I n the first two pairs the total electrolyte concentration was 0.5N and in the last pair A'. The concentrations of the two electrolytes were varied within these limits.For the pair of electrolytes sodium sulphate-sulphuric acid it is shown that the solubility is 5.52 grams per 100 C.C. of 0.5N-sodium sulphate and rises regularly with decreasing sodium sulphate con- centration and increasing sulphurio acid concentration to 7.72 grams per 100 C.C. of 0.5N-sulphuric acid. I n 0.5N-mixtures of sodium sulphate and sodium hydroxide the solubility is constant 5.53 grams per 100 C.C. of solution whilst in the case of sodium chloride and sodium acetate the solubility is 4.62 grams in 100 C.C. of ;2i-sodium chloride and falls regularly to 3.44 grams in 100 C.C. of N-sodium acetate. The electrolytes are seen therefore to have an additive effect. The solubility is also determined in solutions of sodium acetate and sodium chloride of varying concentration and in both cases shown to increase steadily with increasing dilu- tion but in neither case is the depression of the solubility in keep- ing with Steiner's expression.Both sets of solubility values are fairly in keeping with the expression of Hoffmann and Langbeck (A. 1905 ii 374). The solubility of ethyl acetoacetate has been determined in water and solutions of sodium chloride and sodium nitrate of various concentrations a t 16-16*5°. It is shown that 100 C.C. of water dissolve 12.5 grams of ethyl acetoacetate a t 16-16.5O. I n N-sodium chloride 8 . 4 grams dissolve in 100 c.c. and this value increases with decreasing concentration of sodium chloride but the solubility change is in keeping with neither of the above expressions. I n sodium nitrate solution 11.4 grams of ethyl acetoacetate dissolve in 100 C.C. of W-sodium nitrate and the solubility increases in accordance with both the above-named ex- pressions on decreasing the nitrate concentration.The addition Df alcohol to solutions of sodium chloride and nitrate increases the solubility of ethyl acetoacetate in these solvents. * J. F. S. Contrasting Effects of Chlorides and Sulphates on the Hydrogen-ion Concentration of Acid Solutions. ARTHUR W. THOMAS and MABEL E. BALDWIN ( J . Amer. Chem. Soc. 1919 41 1981-1990) .-The hydrogen-ion concentration of a chrome tanning liquor has been determined in the presence of various concentra- tions of sodium chloride ammonium chloride sodium sulphate. ammonium sulphate and magnesium sulphate.The effect of the addition of chlorides is to increase the hydrogen-ion concentration whilst that of sulphates is to decrease it although on keeping the concentration increases somewhat Similar experiments were carried out with pure chromium sulphate solution chromium chloride solution sulphuric acid (0*0005N) hydrochloric acid (0.004A7) sulphuric acid (0.1N). and hydrochloric acid (O.lN) using a number of chlorides and sulphates. In every CWB the chlorides are found to increase the hydrogen-ion concentration andGENERAL AND PHXSICAL CHEMISTRY. ii. 97 The power of increasing the hydrogen- the sulphates to reduce it. ion concentration follows the order MgCl2>BaCl2>LiC1,>NaC1>NH4Cl = KC1. J. F. S. Degree of Ionisation of Very Dilute Electrolytes.GILBERT N. LEWIS and GEORGE A. LINHART ( J . Amer. Chem. SOC. 1919,41 1951-1960) .-A theoretical paper in which the authors deduce a general equation for the freezing-point lowering of dilute strong electrolytes. This equat,ion has the form n h - e / c = p c ~ in which n is the number of dissociated parts h the degree of dissociation 8 the lowering of the freezing point c the concentration and p and a characteristic constants. The calculation and observed values of 0 for fourteen salts a t a series of concentrations are compared and shown to be in good agreement. The thermodynamic degree of dissociation is calculated for the same salts over a range of con- centration 10-1-10-~iV. The constants a and B of the above equation can be obtained from freezing-point determinations.The calculated degree of dissociation diverges extraordinarily from t,he value obtained by the usual method. The Influence of the Dielectric Constant of the Solvent and of the Electric Energy of the Ions on Electrolytic Dissociation MARIO BASTO WAGNER (Anal. Fis. Quim. 1919 16 229-257) .-A purely mathematical paper. Mechanism of Electrolytic Dissociation. B. CABRERA (.4naZ. Fis. Quinz. 1918 16 186-225).-A mathematical paper developing the theory that the ions remlting from the solution of a crystalline substance are already present as such in the crystal the formation of neutral molecules being thus subsequent to the act of solution or fusion. J. F. S. W. S. M. W. S. M. Atomic Constitution of a Crystal Surface. E. MADELUNG (Physikal.Zeitsch. 1919 20 494-496) ,-A mathematical paper in which the author considers the condition of the surface layer of molecules in crystals of the sodium chloride type. It is shown that in crystals of the regular type consisting of binary compounds the atoms of one kind on the surface are displaced in directions at right angles to the surface with respect to the atoms of the other kind. The displacement decreases in the body of the crystal according to a simple exponential equation. It is also shown that since the atoms of electrolytes carry electric charges an electric double layer must in consequence of the displacement surround the crystal surf ace. J. F. S. A New Method of Electrical Synthesis of Colloids. THE. SVEDBERG (Medd. K . Vetensbapsakad. Nobel-lnst.1919 5 NO. 10 l-l8).-The author has prepared gold and silver sols of high dis-ii. 98 ABSTRACTS OF CHER1ICA.L PAPERS. persion by a modified method. The apparatus consists of a quartz tube in which a small hole about 1 mm. diameter is bored. The metal electrodes gold or silver pass down this tube and are so placed that the arc may be formed opposite the hole. The quartz tube is so arranged that a current of nitrogen passes through it both from the top and the bottom. The quartz tube is placed in an outer glass jacket containing about 30 C.C. of the dispersion medium (alcohol) and this jacket is surrounded by a further jacket containing a cooling agent (ice and salt or solid carbon dioxide and alcohol). An electromagnet is placed with its polw on either side of the small hole in the quartz tube.The current (I amp. 220 volts) is switched on and an arc of the usual type appears for about a second then owing to a melting of the lower electrode (anode) the quartz tube becomes somewhat stopped up and so the electrode is protected from the dispersion medium ; the arc becomes a sharp-pointed flame and this is drawn through the hole in the tube by the action of the magnet. Metallic clouds appear and are absorbed by the dispersion medium. The appearance of the arc has been examined spectrographically in both conditions and tthe differences noted. The author holds that the condensation of metal vapour is the cause of the sol formation. Other forms of apparatus are described in the paper. J. F. S. Colloid Metal Reactions. Spectrum Analysis and Blood Colouring Matter.EDUARD RICHTER (Kolloid. Zeitsch. 1919 25 208-211).-A number of colloid react8ions between 1% gold chloride solution and 1 1000 solutions of adrenaline alloxan t+annic acid and p-phenylenedimethyldiamine are described. I n each case colloidal gold is produced but of different degrees of dispersity. From the expesriments i t is deduced that certain diamines possess a particularly powerful reducing action and are probably to be classified with the reducing substances of the amino- group which occur in the animal organism. Certain hydroxy- substances also show a similar reducing action. J. F. S. Colour of Colloids. IX. WILDER D. BANCROPT (J. Physical Chem. 1919 23 554-571. Compare A. 1919 ii 500).-A con- tinuation of the previous discussion.It is shown that with very small particles the light which is ordinarily reflected selectively is transmitted by resonance whilst the light which is ordinarily trans- mitted is scattered. Massive gold is red by multIple reflection and thin films are green by transmitted light. Very small particles reflect green and transmit red light. Massive gold reflects yellow when compact and brown to black when porous. Particles which do not resonate are yellow or brown by reflected light and transmit blue light. Silver is yellow by multiple reflection and thin films are blue to green by transmitted light. Very small particles reflect blue and transmit yellow. Particles which do not resonate transmit blue light and reflect red. Colloidal indigo solutions transmit red light and the surface colour of indigo is red.Sodium fog scattersGENERAL AND PHYSICAL CHEMISTRY. ii. 99 blue light and transmits the yellow which the vapour absorbs. Iodine fog scatters red light. J. F. S. Colours of Colloids. X. WILDER D. BANCROFT ( J . Physical Chem. 1919 23 603-633. Compare A. 1919 ii 500).-A con- tinuation of the previous discussion. In the present paper the colours of glasses and glazes are considered. It is shown that in glasses and glazes gold silver copper platinum iridium oxide selenium tellurium sulphur lead antimonate carbon magnetite ferric oxide stannic oxide zirconium oxide arsenious oxide titan- ium oxide and calcium phosphate occur usually as a second phase. Chromium occurs in some form as a second phase in chrome Aven- turine glass and copper in Egyptian blue.Some glasses coloured by iron chromium manganese and cobalt are optically empty. In enamels the substance causing the colour is probably chiefly adsorbed by the material causing the opacity. J. F. S. Colours of Colloids. XI. WILDER D. BANCROFT ( J . Physical Chem. 1919 23 640-644. Compare preceding abstract).-A con- tinuation of the previous discussion. I n the present paper the colours of gem stones are considered. J. F. S. Coagulation. ARNE WESTGREN (Arkiv. Kern. Min. Geol. 19 18 7 No. 6 1-30).-The coagulation of gold sols has been examined with the object of ascertaining the influence of the size of the colloid particles the nature of the coagulating ions and the temperature on the velocity of the slow coagulation.Forty C.C. of the sol were mixed with 10 C.C. of an electrolyte and after definite intervals of time had elapsed 5 C.C. of the mixture were withdrawn and run into 25 C.C. of 0.5% gelatin solution and the particle concentration deter- mined. Using soh with particles of radius 120 pp 77 p p and 49 pp respectively it is shown that the velocity of coagulation is indepen- dent of the size of the particles. Using the following electrolytes to coagulate the sols (hydrochloric acid sodium lithium potassium and rubidium chlorides sodium hydroxide and sodium iodate) it is shown that the ionic conductivities of the ions are determinative of the coagulating power. Thus hydrochloric acid the cation of which has the greatest ionic conductivity is the most active coagulator of all the chlorides whereas lithium chloride with it3 slow-moving cation is the least active.Potassium chloride and rubidium chloride which have cations of about the same ionic con- ductivity have about the same coagulating power. Since gold sols are negative colloids it follows that when they are coagulated by cations the anions must exercise a stabilising influence and this is shown in the coagulation by sodium derivatives for sodium hydr- oxide with its rapidly moving hydroxyl ion is the least efficient coagulator whilst sodium iodate with its slow-moving anion is the most efficient coagulator. Using hydrochloric acid and sodium chloride at various temperatures it is shown that the velocity of coagulation does not depend on the temperature only because theii.100 ABSTRACTS OF CHEMICAL PAPERS. Brownian movement of the particles depends on it but also because t,he specific coagulation power of the electrolytes changes with the temperature. J. F. S. Effect of the Wall of Vessels on the Velocity of Gaseous Reactions. ELICHI YAMAZAKI (J. Tokyo Chem. Xoc. 1919 40 606-608).-This is a theoretical paper attempting to give an explanation for Kooij's work (A. 1893 ii 569) in which the velocity of dissociation of phosphine was shown to be affected by the nature of the vessel the ratio of the velocity in the new vessel to that in the old being 1 2.25. According to the author the decomposition of phosphine in a vessel should be considered to be a heterogeneous chemical reaction that is (1) a formation of the diffused zone between gas and vessel (2) chemical reaction. I n the new vessel the wall becomes the " diffusion zone," but in the old vessel the decomposition product (phosphorus) adheres t o the surface of the vessel thus creating a larger surface which accelerates the velocity of the diffusion.Ordinarily the velocity of the d3u- sion of the gas over the wall is so fast that only the velocity of the chemical reaction is measured as the total reaction velocity. The author believes that the vessel acts as a catalyst in the same manner as platinum black or sponge by removing the product of the reaction thus maintaining general equilibrium. More detailed investigation and explanation are promised. CHEMICAL ABSTRACTS. An Unsolved Problem in the Application of the Quantum Theory to Chemical Reactions W.C. M. LEWIS (Phil. Mug. 1920 [vi] 39 26-31).-0n applying the quantum theory to a uni- molecular reaction i t is shown that very different results are obtained according as it is assumed that the absorption of radiation is continuous or discontinuous. A very large discrepancy exists in both cases between the calculated and observed velocity con- stants which is much greater on the discontinuous view than on the continuous. This discrepancy is always in the sense that the observed velocity constant is many times greater than the calcu- lated ; on the hypothesis of continuous absorption the observed con- stant is of the order of 107 times greater than the calculafed and also appears to be independent of temperature for different reac- tions.The explanation of this discrepancy is expected to throw light on tthe theory of physicochemical processes. J. R. P. The Propagation of Flame in Mixtures of Methane and Air. I. Horizontal Propagation. WALTER MASON and RICHARD VERNON WHEELER (T. 1920 117 36-47). The Propagation of Flame in Complex Gaseous Mixtures. IV. The Uniform Movement of Flame in Mixtures of Methane Oxygen and Nitrogen. id.Maximum-speed Mixture0" of Methane and Hydrogen in Air. WILLIAM PAYMAN (T. 1920 117 48-58),GENERAL AND PHYSICAL CHEMISTRY. ii. 101 Hydrolysis of Iodoacetic Acid. BROR HOLMBERQ (Medd. E. Vetenskapsakad. Nobel-lnst. 1919 5 No. 11 l-l2).-The velocity of replacement of iodine by hydroxyl in the sodium and barium salts of iodoacetic acid by the action of sodium and barium hydroxidm has been studied; the influence of neutral salts (sodium chloride and iodide and barium chloride) was also investigated.The reaction is bimolecular its velocity being intermediate between those observed for the corresponding bromo- and chloro-acids (com- pare Johansson A. 1912 ii 544). Contrary to expectation there- fore iodoacetic acid is more stable than bromoacetic acid (compare Drushel and Simpson A. 1918 i 57). The effect of the concen- tration of the metal ions on the velocity constant C is given by the equations C=O-lOG[Na*].O*1 and C= 0-220[ba]0*2 where ba=+Ba. The reaction between iodoacetic acid or its salts and silver nitrate was also studied. The formation of silver iodide takes place much more quickly than the production of acid and the author concludm that the most important reactions are represented by the equations ZCH&*CO,’ + Ag’ = CH,I*CO,*CH,*CO,’ + AgI and CH,I*CO,*CA,*CO,‘ + Ag’ = O < ~ ~ z ~ ~ ~ > O + A gI.If the solutions are not too dilute the formation of iodoacetylgly- collic acid takes place much more quickly t*han t’he formation of glycollide. Glycollic acid is then formed indirectly or it may also be formed directly according to the equation CH,I*CO,’ + Ag’ + H,O = OH-CH,-CO,’ + H’ + AgI. T. S. P. Effect of Chlorine on Periodic Precipitation. [Miss] A. W. FOSTER ( J . Physical Chem. 1919 23 645-655).-When silver nitrate is allowed to diffuse into gelatin films cont?aining potassium chromate a series of concentric rings is formed the spacing of which decreases with the distance from the centre.The appearance and spacing of these rings does not depend on the time which Eas elapsed between the formation of the gelatin film and the addition of the silver nitrate. I f however a trace of chloride is present in the gelatin the appearance is altered. Making up the gelatin chromate solution with tap water is sufficient to produce the change. I f such a film is allowed to harden for three hours and then treated with silver nitrate the rings are spiral in form and in groups of three. If a little calcium hypochlorite is added to the gelatin and the film allowed to harden for an hour narrow rings close together are formed by two precipitations. Some Problems in Contact Catalysis. WILDER .D. BANCROFT (Trans. Amer. Electrochem. Soc. 1919 36 reprint).-A number of specific cases of catalytic reactions are cited where a satisfactory explanation of the mechanism of catalysis is not available and further study of these is suggested.Thus the reaction COCl,+ H20 = CO + 2HC1 is so far as is known irreversible. In the pres- ence of excess of water the reaction goes to completion but in the presence of concentrated hydrochloric acid the rate of hydrolysis is J. F. S. VOL. cxvar. ii. 4ii. 102 ABSTRACTS OF CHEMICAL PAPERS negligible. A theory is suggested but study is necessary to prove it. Also trichloromethyl chloroformate (superpalite) reacts as follows in the presence of alumina CCI,*O*COCl=CO,+CCl and in the presence of ferric oxide CCl,*O*COCl= 2COC1,. The reverse reac- tion has never been made to take place to any extent.Yet when some superpalite and ferric oxide were placed in a tube the reaction sGon came to an apparent end. When the temperature was raised a little the reaction went further and did not reverse on cooling. It is suggested that this phenomenon was due to poisoning of the ferric oxide. Finally some experiments by Lind are cited which may if desired be regarded as the displacement of an equilibrium by a catalytic agent. If radium emanation is placed in water in the liquid phase hydrogen and oxygen are formed and escape into the vapour phase; if the emanation is moved up into the vapour phase oxygen and hydrogen are caused to combine. Additional examples are cited and some interesting lilies of experiments suggested. CHEMICAL ABSTRACTS. Catalytic Decomposition of Hydrogen Peroxide.GOSTA PHRAGM~N (Medd. K . Vetenskapubud. Nobel-Inst. 1919 5 No. 22 1-13).-The rate of decomposition of hydrogen peroxide in alkali phosphate or sodium hydroxide solutions has been determined a t 17-18O. I n the phosphate mixtures it is shown that the reac- tion velocity reaches a maximum at P,=11-8. I n alkaline hydr- oxide solutions the velocity is not easily reproducible and some- times gives a large value and sometimes a small value. Since the velocity decreases with both increasing and decreasing hydrogen- ion concentration it is assumed that hydrogen peroxide forms a salt with sodium hydroxide which is verv stable and that only the undissociated hydrogen peroxide molecules undergo decomposition. The decomposition of hydrocen peroxide by yeast extract in the presence of a phosphate buffer mixture has been determined at 17-18O.It is shown that fresh yeast decomposes dilute hydrogen peroxide without sending a soluble enzyme into the surrounding liquid. The reaction is of the first order between certain limits and the reaction coefficient increases proportionally to the quantitp of yeast. The catalytic action per cell or per gram can he increaFed by treating the yeast with sugar solution before use. Ths reaction constant is no criterion of the quantity of cat-alase in the cells. J. F. S. Catalytic Actions at Solid Surfaces. 11. Transference of Hydrogen from Saturated to Unsaturated Organic Compounds in the Liquid Staye in Presence of Metallic Nickel E. F. ARMSTRONG and T. P. HILDITCH (Proc.Roy. SOC. 1919 [ A ] 96 322-329. Compare A. 1919 ii 403).-The evidence that metallic catalysts during the hydrogenation process interact primarily with the unsaturated organic compound together with the resemblance of the whole process t o enzyme action (Zoc. c i t . ) led to the consideration whether the catalytic action like thatGENERAL AND PHYSICAL CHEMISTRY. ii. 103 of certain enzymes might not be reversible. Evidence in support of this view has no’w been obtained. A t 180° an equimolecular mixture of cyclohexanol and methyl cinnamate may in the presence of nickel be transformed into one in which about 10% of the cinnamic ester has become hydrogenated to methyl P-phenyl- propionate the cyclohexanol being transformed into cyclohexanone. The experiments indicate that it is necessary that both components of the system should be present in the liquid state. A similar action took place to a certain extent at 230° when the cyclohexanol was replaced either by dimethylcyclohexane or bv dihydropinene.Similarly a mixture of ethyl stearate aqd methyl cinnamate when heated at 230° with catalytic nickel gave a product containing small quantities of methyl /3-phenylpropionate and ethyl oleate. An important point to note is that simultaneous dehydrogenation and hydrogenation have now been effecte,d at temperaturw not far removed from the general optimum hydrogenation range (170-180°) and that hydrogen has been transferred from one compoun’d to another instead of from one molecule to another of the same species as was observed by Zelinski and Glinka (compare A 1911 i 870).There is no absolute proof that the mechanism of the change is not dependent on the production of hydrides of nickel but the aut-hors prefer to regard it as a further case of the catalytic equilibria previously discussed which may be indicated as follows +Ni [ c::EZ:Ni] Saturated compound Unsaturated compound Ni Unsaturated + Ni + H,. [ hydrogen 1 - compound The ultimate equilibrium will depend on the resultant of the vary- ing affinity for nickel of the saturated and unsaturated compounds involved. This view of catalytic hydrogenation and dehydrogenation affords some explanation of the products obtained (compare Moore J . Sac. Chem. Tnd. 1919 38 3 2 0 ~ ) during the hydrogenation of un- saturated glycerides where partial isomerisation occurs.It is suggested that in the hydrogenation of ethyl oleate a portion of the freshly produced ethyl stearate in contact wit.h the nickel under- goes dehydrogenation the hydrogen liberated being transferred to more ethyl oleate the ‘‘ dehydrogenated ethyl stearate ” formed being the ethyl AX-oleate isolated by Moore (Zoc. cit.). Constitution and Structure of the Chemical Element. RAWKSWORTH COLLINS (Chem. News 1919 119 295-296).- Single electropositive charges emanate from masses of 1 (hydrogen) 7 (lithium) 23 (sodium) and 39 (potassium) also two electro- positive charges emanate from 4 (helium) of which one has been shown to emanate from a mass 3 (H3) hence single electropositive charges emanate from masses 1 3 7 23 39. Taking the first twenty-six elements it is shown that twenty of these may have their W.G . 4 *ii. 104 ABSTRACTS OF CHEMICAL PAPERS. atomic weights split up into the above-named numbers in such a way that the number of parts is the same as the maximum valency. All the parts are odd numbers and the non-metallic elements are characterised from the metallic by the presence of one or more portions (1 + 3) (helium). Elect>ropositive forces are distinguished from electronegative forces by the following rule an electropositive force emanates from each of the masses 1 3 7 23 39 except when an element has one or more portions (1 + 3) in which cases electro- positive forces emanate from these portions whilst electronegative forces emanate from each of the remaining portions of the element.Hydrogen forms the connecting link in the structure of these elements. From tables given in the paper it is shown that the longer the chain of -H-H the more volatile the element and the stronger the electronegative forces from the metallic portions. On this basis the structure of the sulphur atom is given as I I I * Na-H-H3-H-H,-H I I in which Na represents 23 H represents 1 and H 3. The thick lines represent electropositive charges the curly lines electronegative charges and the thin lines forces which are not chemically evident but which have to be overcome before the element can be dis- integrated. The atomic number of sodium is 11 that of H and H unity which makes the atomic number of sulphur 16 which is in keeping with fact. The formula therefore shows the connexion between atomic weight atomic number and maximum valency and distinguishes between electroposit,ive and electronegative charges.The molecule K,SO may therefore be represented OK OK 0 /\ Na-€3-H,-H-H,-H. \/ 0 J. F. S. A Model of Radioactive Atoms. TORAHIKO TERADA (Proc. Phys. Math. SOC. Japan 1919 [3] 1 185-195).-According to the recent view of atomic structure an atom consists of a positive nucleus about which a number of electrons are revolving. The conception of the positive nucleus is slightly extended by consider- ing the case of two heavy nuclei with opposite charges revolving about the common centre of mass. Assuming a primary with the larger mass having a positive resultant charge and the secondary of smaller mass charged negatively as a whole and leaving out of consideration the ring electrons i t is evident that the two members of the nuclear system will exert on each other a mutual action analogous to the tidal action in the case of the gravitating planetary system.Both members are considered to consist of a number of positive and negativel elementary charges bound together by some unknown forces; also most of the positive charges are assumed toGENERAL AND PHYSICAL CHEMISTRY. ii. 105 consist of two elementary charges as in the case of a-part-icles. When the tidal action exceeds a certain limit the secondary may become unstable and when the elementary charges in the two substances happen to take a definite configuration one of the charges may escape and be projected from the nuclear system with the momentum possessed during the orbitual motion.If the negative secondary loses a positive charge by the expulsion of an a-particle the attraction of the primary will increase and the orbitual velocity be accslsrated. I n actual radioactive transformations the veloci- ties of the expulsion of the a-particles generally increase with successive transformations although with some exceptions. The tidal action will increase with the decreasing distance bet<ween the two nuclei and consequently the chance of disruption will increase because the chance of the a-particle stepping out of the critical threshold will increase. The result will be the shortening of the life of the atom in question. This seems to suggest a possible way of explaining Geiger and Nuttall's law concerning the relation between the average lives of radio-elements belonging to a dis- integration series and the velocities of the a-particles emitted from these elemeats.If the two members of the nuclear system gradu- ally approach each other by successive emission a stage may be attained a t which the two substances are amalgamated into one pro- vided the resulting configuration is a stable one. When this final stage is reached the disintegration will be stopped and the end- product of the radioactive transformation will be reached. One of the simplest systems conceivable is proposed as a provisional work- ing model and the consequences tested in the light of the available experimental data. CHEMICAL ABSTRACTS. Metals and Non-metals.A. SMITS (Proc. I<. Akad. Wetensch. Amsterdam 1919 22 119-125).-The author explains the posi- tive charge of the chlorine electrode by assuming that the chlorine atom has the power of splitting off and absorbing electrons and further that these two processes can take place side by side. This is represented by the equations XCl dX(31,' + 2XOG and YCl,,+2YO S 2YClG' in which X and P indicate the frac- tions of the chlorine molecules which have undergone positive and negative ionisation respectively. As the electrons which are absorbed in the second action proceed from the first it is clear that Y Z X but chlorine being a non-metal both fractions must be extremely small. If then i t is further assumed that the negative ions almost exclusively pass into solution the electrode will then possess a positive charge.Extending the above hypo- thesis the author shows that t-here is only a difference of degree between metals and non-metals and not one of kind. If it be assumed that all elements can both split off and absorb electrons then t-he factor X is comparatively large for metals and small for non-metals and for non-metals P is exceedingly small. This view is in keeping with the large electric conductivity of metals and the small cmductivity of non-metals. In the case of the metals the 4"-2ii. 106 ABSTRACTS OF CHEMICAL PAPERS. positive ions have the greater solubility and the negative ions in the case of the non-metals. This is in keeping with the different electromotive behaviour of metals and non-metals. The difference in solubility between the two ions is so great as to justify t-he assumption that only one kind is present in solution.Amphoteric elements probably send appreciable quantities of both positive and negative ions into solution. J. F. S. Atomic Structure and the Periodic Law. TYCHO E:SON AURBN (Medd. K. Vetenskapakad. Nobel-Inst. 1919 5 No. 18 1-7) .-A theoretical paper. The author’s experiments on the absorption of Rontgen rays (details not yet published) indicate the possibility of differentiating between the inner and outer elect,rons in the atom the outer electrons being identical with t.he so-called valency electrons and playing a totally different r61e from the inner electrons. I n accordance with this view Kossel’s table (A. 1916 ii 243) for the first twenty-three elements of the periodic system is modified._The number of electrons in the outer ring increases from one in the case of hydrogen to seven in the case of nitrogen; it does not become eight in the case of oxygen but four electrons go from the outer ring to tvhe inner system; the number of outer electrons then increases to seven again for sodium whilst for mag- nesium four more electrons go from the outer to the inner system and so on. The consequences of these conceptions are discussed special reference being made to the valencies of the elements in the various groups. For example it is argued that sulphur should be bivalent; the existence of SO and SF is no definite proof of the sexavalency of sulphur since the former can be represented by a ring structure and the latter as :>F.S.F<g.T. S. P. Atomic Numbers HAWKSWORTH COLLINS (Chem. News 1919 1 19 285-287) .-The author considers the atomic weights (nearest whole number) atomic numbers and valencies of the first twenty-eight elements taken in order of their atomic weights. It is shown that with four exceptions (glucinum nitrogen scandium and cobalt) when the atomic weight is represented by an even number the maximum valency and the atomic number are both represented by even iiumbers and when the atomic weight is repre- 3ented by an odd number the valency and the atomic number are also represented by odd numbers. Further the elements with the exceptions named follow one anot-her alternately odd and even. The probability that this condition of things has happened accident- ally is 1 :42*. The reason for the odd and even rule is shown to be as follows. If the atomic weight of an element be split up into 3’s and 1’s alternately always commencing with a 3 the number of portions obtained gives the atomic number and should the atomic number be an even number the atomic weight must of necessity be an even number but if the atomic number is odd the atomic weight must also be odd. The atomic number is exactlyGENERAL AND PHYSICAL CHEMISTRY. E 107 obtained as follows. If the atomic weight is an even number the atomic number is onehalf of the atomic weight but if the atomic weight is an odd number the atomic number is onehalf of the atomic weight from which 1 has been subtracted. J. F. S. The Mathematical Possibility of Increaaing the Yield or of Reducing the Proportion of the Reacting Substances in certain Chemical Reactions. ANGEL PBREZ HERNANDEZ (Anal. Fis. Qzcim. 1918 16 302-317) .-An ele,mentary mathe- matical method is illustrated for the constz-uction of chemical equa- tions in which two or more reactions are simultaneously involved. W. S. M. Some Biographical Notes on Hermannus Follinus. W. P. JORISSEN (Chem. JVeekbZad 1919 16 947-951).-The biographer gives a very brief sketxh of Hermannus Follinus who was born in Friesland circa 1590 and joined the medical faculty in Cologne where he died of the plague in 1622. He was the author of “Den Nederlandtsche Sleutel van’t Secreet der Philosophie ” (Key to the Secrets of Philosophy) “ Physiognomie,” and “ Simonides ofte die Memori-const ” (Science of Memory). W. J. W. An Apparatus for Preparing in a Very Short Time Homogeneous Liquid Mixtures. PIERRE JOLIROIS (Compt. rand. 1919 169 1095-1098).-A simple apparatus is described consistr ing essentially of two containers one for each of the liquids to be mixed arranged so as to deliver into the two limbs of a Y-tube of the pattern shown the liquids in the requisite proportion. The diameter of the Y-tube is 6.2 mm. and the M lower limb has a restriction as shown 1.5 mm. in diameter and 2 cm. long. With such an ap- paratus a homogeneous mixture may be obtained U from two miscible liquids in 1/100th of a second. W. G . Eykman’s Suction Pump. L. TH. REICHER (Chem. Weekblad. 1919 16 951-956).-This apparatus embodies the principle of Geissler’s suction pump but the operation of filling the vessel in communioation with the apparatus which has to be exhausted by lifting a second vessel periodically is avoided. Special features of Eykman’s pump are a “ vacuum reservoir,” containing air-free concentrated sulphuric acid and a drying device also filled with that liquid. A sketch of the complete apparatus is given and its mode of operation described. W. J. W.

ISSN:0368-1769    

DOI:10.1039/CA9201805069

出版商:RSC    

年代:1920

数据来源: RSC

摘要:

ii. 108 ABSTRACTS OF CHEMICAL PAPERS. Inorganic Chemistry. Model of a Triatomic Hydrogen Molecule. N. BOHR (Medd. K . Vetenskapsakad. robel-lnst. 1919 5 No. 28 1-16).-A theo- retical paper in which it is shown that triatomic hydrogen consists of three nuclei and three electrons. The electrons rotate at equal angular intervals in a common circular orbit whilst the three nuclei are placed on the axis of this orbit. It is shown that H3 cannot. be formed from molecules without the supply of energy from external sources. On the other hand it is shown that in hydrogen gas which is ionised by external agencies molecules of H may be formed by successive processes each of which is accompanied by the production of heat. The Solubility of Sulphur Dioxide in Sulphuric Acid. FRANK DOUGLAS MILES and JOSEPH FENTON (T.1920 117 Some Points of View concerning the Nitrogen Question and Related Problems. L. HAMBURGER (Chem. Weekblad 191 9,16 560-595).-An amplified version of a lecture delivered before the Algemeen Bestuur der Nederlandsche Chemische Vereeniging on July l?th 1918. Electrochemical Reactions of Nitrogen and the accom- panying Spectroscopic Phenomena. L. HAMBURGER (Chem. Weekblad 1918 15 931-942).-A mixture of nitrogen and hydro- gen in stoicheiometrical proportions under a pressure of 12 mm. af mercury was passed through a quartz capillary tube and subjected to a direct-current discharge of 1 2 amperes per square cm. A yield of 109 mg. of ammonia per kilowatt-hour was obtained. Reduction of the current density and simultaneous increase of the time of exposure to the discharge gave mu& smaller yields.The conditions for a high yield of ammonia thus correspond with those necessary for the formatioc of activated atomic nitrogen and hydrogen. The discharge through mixtures of nitrogen with hydrogen oxygen and carbon monoxide was examined spectroscopically. I n every case evidence af the disruption of the molecules and formation of new compounds such as cyanogen was obtained. EUGBNE WOURTZEL (Compt. rend. 1919 189 1397-1400).-As a result of measurements at temperatures between Oo and 86.5O it is shown that the variation of the dissociation constant with the temperature is given by log El T = 8.9908 - 2810.5 / T and calculated from this the heat of polymerisation is 12,850 cal. exact t o 0.5%.Luminescence and Ionisation in the Oxidation of Phosphorous Oxide. HERMAN RINDE (AT& Kern. Min. Geol. 1917-18 7 No. 7 1-21).-A mixture of oxygen and carbon J. F. S. 59-61). W. S. M. W. S. M. The Dissociation Constant of Nitrogen Peroxide. W. G.INORGANIC CHEMISTRY. ii. 109 dioxide dried by means of sulphuric acid calcium chloride and phosphoric oxide and warmed to a suitable temperature is passed through two absorption bulbs containing phosphorous oxide with the vapour of which it becomes saturated. No luminescence takes place with the dried gas but when the mixture is led over the surface of water contained in a tMt-tube luminescence appears. The absorption bulbs and test-tube containing water were immersed in a thermostat a t constant temperature and the total intensity of the luminescence was measured photographically by means of a Martens’ photometer. There is no luminescence in pure carbon dioxide but the addition of oxygen causes the phenomenon to appear and its intensity is greatest in mixtures containing 5% of oxygen.With increase in the percentage of oxygen the intensity decreases and attains an approximately constant value between 50% and 100% oxygen (com- pare Scharff A. 1908 ii 373). When a tube 3.75 metres long is inserted between the absorption bulbs and the tesbtube the intensity of the luminescence is about the same for mixtures containing a low percentage (about 5%) of oxygen but it rapidly diminishes with increasing oxygen content to a lower value than before the tube w~ts inserted. At the same time t.he tube becomes covered with a deposit of phosphoric oxide.These results indicate that the phos- phorous oxide is oxidised without luminescence by the dry oxygen and that the diminished luminescence with mixtures containing high percentages of oxygen is due t o the fact that the gas coming into contlact with the water-vapour contains much less phosphorous oxide. According to Scharff (Zoc. cit.) the merest trace of water-vapour is sufficient to cause luminescence but €he author finds that when the vapour pressure of the water-vapour is diminished as for example by using concentrated sulphuric acid instead of water the luminescence becomes very feeble. As with all gas reactions the width of the test-tube containing the water affects the intensity of the luminescence.The wider the test-tube the less the luminescence. The author suqgwts that> in dry oxygen phosphorous oxide is directly oxidised t o phosphoric oxide but that in moist oxygen an intermediate compound X is formed according to the equation Ionisation does not occur in a gas free from oxygen but contain- ing phosphorous oxide. In the presence of oxygen ionisation takes place and the author has measured the saturation current (compare Harms A. 1904 ii 331; Bloch A. 1905 ii 72). The ionisation is not a photoelectric effect as shown by measurement of the satura- tion current with different electrodes but is caused by the oxidation of an unknown intermediate product formed from phosphorous oxide and water vapour. Th3 mobility of the ions is small corn- pared with that of ordinary gaseous ions but of the same order as that obtained for the ions formed in the oxidation of phosphorus (ccmpare Harms and Bloch loc.cit.) and it is very probabIe that the isns are produced by the same reaction in both cases. T. S. P. P,O t; RpO + 0 + X + HSPO,.ii. 110 ABSTRACTS OF CHEMICAL PAPERS. Some Chemical Characters of Ancient Charcoals. T. C CANTRILL (Archaeol. CambrensG 1919 365-392) .-Although the pieces of charcoal or charred wood found during archzeological exca- vations are more readily attacked or dissolved by such reagents as nitric acid and potassium chlorate and hypochlorite solution thus differing from modern well-burnt charcoal the author considers that the solubility etc. of some of the ancient charcoals is simply due to their incomplete carbonisation and that there is doubt that they were produced by the agency of fire.The situations in which certain of the charcoals are found negatives the opinion that the blaokening of wood was due t o the action of peaty soil. Artificial Production of Diamond. SIR CHARLES A LGERNON PARSONS (Phil. Trams. 1919 A 220 67-107).-Bakerian lecture. It is shown from experiments that all the hydrocarbons chlorides of carbon and oxides of carbon deposit amorphous carbon or graphite on a carbon rod electrically heated at any pressure up to 4400 atms. and in a few cases up to 6000 atms. A t 15,000 atms. carbon and graphite electrically heated are either transformed into soft graphite or are first vaporised and condensed as such. The experiment of compressing a mixture of acetylene and oxygen and the production of a temperature in excess of that required to vaporise carbon accompanied by a momentary pressure of 15,000 atms.shows that the failure to convert graphite into diamond is not due to lack of temperature. The experiment of firing a high-velocity steel bullet with cupped nose through vaporising carbon into a hole in a block of steel raises the pressure moment>arily to 300,000 atms. and the temperature probably 1000° but the fact that only a few minute crystals resembling diamond were produced (probably from the iron) leaves a doubt as t o whether the duration of the pressure was sufficient to start a recogn'lsable transformation of graphite to diamond. A repetition of many of the experiments in which diamond has been claimed to be formed has given negative results except where iron has played a part.A list of the experiments tried together with conditions and results is given in an appendix to the paper. In repeating Moissan's experiments i t is shown that when a crucible of molten iron is subjected to pressure more than three times as great as can be produced by these contractile forces the yield of diamond is not increased; on the other hand if the ocoluded gases are imprisoned then the yield of diamond is about the same as when the crucible is plunged into water whilst if the conditions are such as to allow a free passage of the gases through the skin of the ingot the yield is a t once reduced even though the bulk pressure on the ingot is the same.Experiments in vacuum from 75 mm. to X-ray vacuum show generally that as the pressure is decreased the yield of diamond is diminished and below 2 mm. no diamond could be detected. The greatest percentage of diamond ocourred when the atmosphere round the crucible consisted of 95% carbon monoxide 1% Kydrogen 2% hydrocarbons 2% nitrogen. The weight of diamond is about 1/20,000 of the weight of the iron. It appears that the formation of diamond in rapidly cooling iron takes W. P. S.INORGANIC CHEMISTRY. ii. 111 place when i t is solid or in a plastic condition or even a t a lower temperature. The rapid Fitting of a diamond in highly carburised iron just above its melting point is so pronounced that the largest diamond hitherto produced artificially would be destroyed in a few seconds if the iron matrix were molten.The experiments indicate that the bulk pressure on the metal dues not play a part in the formation of diamonds but that the previous heat treatment the impurities in the iron and the condition of the gases within the metal are the important factors. The iron in the most successful experiment has a concentration of diamond 270 times as great as the blue ground in the South African mines. Production of Carbon Monoxide in the Flames of Gases. ANDRB KLING and DANIEL FLORENTIN (Compt. rend. 1919 169 1404-1406).-A number of gases the carbon monoxide content of which varied from 0% to 60% were burnt a t differing types of burners in a large chamber and the carbon monoxide in the air waa estimated at the end of one hour. The results indicate that the pro- duction of carbon monoxide is due principally to the sudden cooling of the flame.For a given type of burner the amount of carbon monoxide present in the gas to be burnt is without influence on the amount present in the products of combustion. The Auer burner produced comparatively large amounts of carbon monoxide this production being due apparently to the presence of the incandescentt mantle. The hourly production of carbon monoxide with certain common types of burners is sufficiently high to warrant further efforts to improve them. Atomic Structure oi Metals in Solid Solution. A. L. FEILD (Chem. and M e t . Eng. 1919 21 566-570).-The reason for the difference in physical properties of solid solution alloys and their components has been investigated.It is concluded that the alloys retain in the solid state the same atomic structure as in the liquid state the metals being in the amorphous form. Such a solid solution is analogous to a supercooled liquid with the same electrical resistance and temperaturecoefficient of resistance as in the molten state. Experiments with alloys of nickel and chromium and of gold and silver confirm this theory. It does not apply to eutectic alloys. The hardness of alloys is also ascribed to an amorphous state. J. F. S. W. G. W. J. W. Transition of Dry Ammonium Chloride. ALEXANDER SMITH HERBERT EASTLACK and GEORGE SCATCHARD ( J . Amer. Chern. SOL 1919 41 1961-1959).-Time-temperature curves both heating and cooling have been made for absolutely dry ammon- ium chloride with the object of ascertaining whether the dry mate- rial changes into a second crystalline form a t 184*5* as does the undried material.It is shown that ammonium chloride which has been dried for forty-five days at 155+165O or for three years with phosphoric oxide in a high vacuum undergoes exactly the same transition a t 184.5' as the undried salt. In the thermal measure- 4**ii. 112 ABSTRACTS OF CHEMICAL PAPERS. ment of transition points in a high vacuum confusion may result from the greater thermal effects of distillation. Wegscheider’s explanations of the anomalous vapour density of dried ammonium chloride by a failure to undergo transition in the absence of water are untenable in the light of these resu1t.s (A. 1918 ii 298). J. F.S. Lithium Silicate. K. ALB. VEBTERBERG (Nedd. K. Vetens- kapsakad. Nobel-Inst . 1919 5 No. 30 1-9) .-Amorphous silicic acid which has been dried a t looo dissolves slowly in a fairly con- centrated (approx. 2N) solution of lithium hydroxide a t the ordin- ary temperature giving finally a solution containing 3.4 mols. of SiO to 1 mol. of L&O. Thus lithium behaves similarly to potassium and sodium in giving soluble silicates containing a large excess of acid over the base (oompare A. 1915 ii 344; also Jordis and Ranter A 1903 ii 475 542 595; Jordis 1908 ii 291; Ordway 1908 ii 37). In warm lithium hydroxide solution however silicic acid is almost insoluble the acid being transformed into a practi- cally insoluble lithium silicate. Lithium metasilicate occurs in two modifications the one easily soluble and the other almost insoluble.The latter which has the formula Li2Si03,H20 is obtained as a white granular precipitate when a fairly concentrated solution of sodium metasilicate is mixed with the equivalent quantity of lithium chloride lithium hydroxide added in approximately normal concentration and the solution heated for a short time a t 80-90°. It can also be obtained by dissolving silicic acid which has been dried at a temperature not higher than looo in twice the theoretical amount of 2N-lithium hydroxide solution a t the ordinary temperature and then heating the solution for a short time a t 80°. T. S. P. A New Physicochemical Method of Analysis of Precipi- tates. Application to the Study of the Calcium Phosphates.PIERRE JOLIBOIS (Compt. rend. 1919 169 1161-1163).-The two solutions from which the precipitate is obtained are very rapidly mixed by means of the apparatus previously described (this vol. ii 107) and the precipitate is collected and analysed and the super- natant liquid is also analysed when equilibrium has been reached. Applying this method to the study of mixtures of solutions of calcium hydroxide and phosphoric acid in varying proportions the author has prepared and characterised a new calcium phosphate having the composition 2Ca0,P20,,3Ca0,P20,,10H20. This phos- phate ocmrs in a crystalline form and in the presence of excess of phosphoric acid is slowly converted into the dicalcium phosphate. W. G. Research on Magnesia Alba by Joseph Black Petrus Driessen and Others.W. P. JORISSEN (Chem. Wsekblad 1919 16 1579-1589).-The author gives a retrospect of the researches of Joseph Black on magnesia alba which led to his discovery of carbon dioxide (“.fixed air ”). The niet.hods of preparation ofINORGANIC CHEMISTRY ii. 113 magnesia alba described in the literature 011 the subject are varia- tions of the original experiments of Black Driessen and other investigators of the eighteenth century. W. J. W. Zincates of Sodium. Equilibria in the System Na,O-ZnO-H,O. F. GOUDRIAAN (Proc. K. Akad. Wetensch. Amsterdam 1919 22 179-189).-The solubility isotherm in the system N+O-ZnO-H,O has been completely determined a t 30' by dissolving zinc oxide in solutions of sodium hydroxide of various concentrations and determining the solubility.The following sub- stances appear as stable solid phases zinc oxide sodium zincate N+0,Zn0,4H20 and the monohydrate of sodium hydroxide. Sodium zincate forms very strongly incongruent solutions ; in solu- tions containing 1 part of sodium hydroxide to 2 parts of water it is decomposed with separation of zinc oxide. Amorphous gelatinous zinc hydroxide is to be regarded as a phase of a varying water con- tent; it is impossible to remove all adsorbed ions from it and i t is metastable as regards zinc hydroxide. I n special circumstances zinc hydroxide may be obtained as a crystalline phase of the constant composition Zn(OH),. This crystallised hydroxide is metastable at 30° with respect of zinc oxide. J. F. S. Reguline Lead Peroxide. WILH. PALMAER (Medd.K. Vetenskapsakad. r'Vobel-Inst. 1919 5 No. 31 1-15).-Compact lead dioxide has been prepared by the electrolysis of lead nitrate solution. The product is greyish-black in colour and has a pro- nounced crystalline appearance and contains no impurities ; it has a hardness 5-6 and D 9.360. I n all respects it is similar to the mineral plattnerite. The specific resistance a t 1 8 O is 0*000845 ohm and the specific conductivity 1180 ohm-1. The temperature- coefficient of the conductivity is 1/8% per degree. J. F. s. Aluminium Spontaneously Oxidisable in the Air. E. KOHN-ABREST (Compt. rend. 1919 169 1393-1395) .-Attention is drawn to the fact that when aluminium is distilled in a vacuum a t llOOo the globules of aluminium remaining undistilled a t the end of sixteen to twenty hours when exposed to the air a t the ordinary temperature undergo spontaneous oxidation giving a yellowish-grey powder which is a mixture of the oxide and the finely divided metal.This aluminium only contained 0.4% of iron and 0.5% of silicon. W. G . Chemical Method for the Determination of the Strength of Sparingly Soluble Inorganic Bases. K. A. VESTERBERG (Arkiv. Kern. Min. Geol. 1917 6 No. 11 1-20).-The deter- mination of the hydrolysis of salts of sparingly soluble inorganic bases by electrometric methods and methods depending on the inversion of sucrose or the hydrolysis of esters has given very vary- ing results according to the methods used (compare Denham T. 1908 93 41; Lund&n A. 19Oe ii 164). Farmer's method (T. 4*"-2ii. 114 ABSTRACTS OF CHEMICAL PAPERS.1901 79 863) for the determination of hydrolysis does not give correct values owing to the disturbance of the hydrolytic equil- ibrium by the partial extraction of the one product of hydrolysis. I n the case of cobalt acetate for example too little acetic acid is extracted. The1 author makes use of Farmer's method but modifies and corrects it as follows. The solution is extracted with twice its volume of ether; t-he same et'hereal solution is again used to extract half its volume of a fresh solution of cobalt acetate. This process is repeated until the concentration of the ether phase becomes constant with respect to aceltic acid showing that i t is in equil- ibrium with hydrolysed cobalt acetate solution in which base and acid are present in equivalent proportions.Ths percentage hydro- lysis can then be readily calculated. Usually the concentration of the ether phase becomes constant after three extractions. Corrections have1 to be made for the increase in volume of the aqueous phase by solution of et.her and the ether and salts used have to be specially purified. I f the acetate is difficult to obtain pure accurate results can be obtained by using a solution of the sulphate or nitrate to which an equivalent- quantity of sodium acetate has been added. The determinations were carried out a t 1P the distribution coefficient of acetic acid between ether and water being taken as 2.1. The results obtained for percentage hydrolysis were as follows AT/2-cobalt acetate 0.19; N/5 0.165 ; NI2-nickel acetate 0.435; N / 5 0.38.It follows that cobalt hydroxide is a stronger base than nickel hydroxide and this agrees with the stabilities of their sulphates. The fact that the hydrolysis is greater in the stronger solutions may be due to the greater salting-out effect of the acetate on the acetic acid. The hydrolysis of lanthanum acetate in NIEi-solution was 0.315% and in N/lO-solution 0.286% the value 0.31% being taken as correct for both solutions the differences being within the error of experi- ment. Lanthanum acetate was found to have 1$H,O of crystal- ligation the solubility a t 180 being 20.43 grams of the anhydrous salt in 100 grams of water; it loses &H,O a t looo. T. S. P. A New Complex Form of Chromic Sulphate. A. RECOURA (Compt. rend. 1919 169 1163-1166).-When a N/2-solution of chromic sulphate is allowed to remain until equilibrium is reached in so far as the formation of the green sulphate is concerned and then evaporated to saturation point in a vacuum on the addition of an excess of alcohol a lilac-grey precipitate is formed.If this precipitate is immediately collected and washed with a litt.le ether it is found to contain 18H,O and to have the whole of its "SO precipitable by barium chloride. It changes however spon- taneously and rapidly when exposed to the air and at the end of the day contains only 16H20 and gives no precipitate with barium chloride. If left in a desiccator. its wakr content finally drops to 12R,O. The constitution of this new complex sulphate has not yet been determined. W. G.INORGANIC CHEMISTRY.ii. 115 Method of Obtaining and Optical Study of Crystals of Sodium Chromate Tetrahydrate. LUCIEN DELHAYE (BUZZ. SOC. franc. min. 1918 41 80-92) .-Deliquescent monoclinic crystals 5 mm. in length can be obtained by allowing a solution of sodium chromate saturated a t 50° to cool to about 27O filtering and keep- ing for several days with occasional shaking. The refractive indices optic axial angle dispersion etc. have been measured for light of various wave-lengths. CHEMICAL ABSTRACTS. Chemistry of Quinquevalent Tungsten. OSCAR OSON COLLENBERG (Ark& Kem. Min. Geol. 1918 7 No. 5 1-35).- Solutions of tungstic acid and alkali tungstates in oxalic acid or alkali oxalate solutions are readily reduced t o quinquevalent tungsten derivatives. From the solution of tungstic acid in oxaIic acid pure solid reduction products could not be isolated but if the solution is saturated with hydrogen chloride and then treated with a solut.ion of rubidium chloride in concentrated hvdrochloric acid the compound diruhidium pentnchlorotungstite Rb,WOCl crystallises out in very good yield.When a solution of an alkali tungstate in oxalic acid solution containing a slight excess of alkali oxalate is reduced with tinfoil the colour passes through dark blue and becomes green yellowish-green and finally red. On cooling the highly concentrated solution oxalic acid alkali oxalate and tin oxalate separate. The tin is removed by hydrogen sulphide from the solution and on adding alcohol a dark reddish-brown powder separates. On dissolving the powder in water and addinp; an excess of alkali iodide or bromide it is obtained pure.I n this way the ordo-tunnstites of wodium. potassium and ammonium have been prepared. whilst the sodium salt is similar except that it contains 12H,O. The oxalo-tungstites are suitable substances for the preparation of other auinquevalent tungsten derivatives. They dissolve readily in hydrochloric acid to produce deep blue solutions from which the oxy-chlorides of quinquevalent. tungsten may be separated. Thev are soluble in potassium thiocyanate solution producing deep red- coloured solutions ; they dissolve in concentrated hydrofluoric acid solution producing violet solutions. On boiling with potassium cyanide yellow solutions are obtained from which double cyanides of the type M4W(CN)8 may be isolated.The alkali oxalo-tungstites may be converted into chloro-tungstites by the following methods (a) by treating the hydrochloric acid solution of an alkali (K or NH,). oxaletungstite with hydrogen chloride ( b ) by adding chlorides (rubidium cesium aniline tetraethglammonium and tetrapropylammonium) to t,he hydrochloric acid solution of an oxaletungstite and ( c ) by adding either pyridinium chloride or quinolinium chloride t o a solution of ammonium chloro-tungstite in concentrated hydrochloric acid. By these methods derivatives The potassium salt has the formula 3K90,2 W,0,,4Cz0,,9HoO of the types (i) M?WOCl,(M =NH,. Rb Cs C,H,*NH3) (ii) M,WOCl,,zH,O(M =K),ii. 116 ABSTRACTS OF CHEMICAL PAPERS. (iii) MWOCl,(M = C,H,NH C,H,NH) and (iv) MWOCl,,H,O(M = [C2H5],N [C,H,],N) have been prepared.All the derivatives obtained have been shown by titration with potassium perman- ganate or by titration with iodine and arsenious acid to contain the tungsten in the quinquevalent condition. The chloro-tungstites are finely crystalline powders; they are quite stable in dry air but a t 60-70* are oxidised turning blue and eventually quite white. They are hydrolysed by water and a reddish-brown hydroxide is produced. I n the case of the less soluble compounds for example the esium salt C%WOCl the hydrolysis is not. complete. The chloro-tungstites are soluble in concentrated hydrochloric acid and in the case of the metal derivatives the solubility decreases with increasing atomic weight; t-hey are insoluble in most organic solvents excent in the case of the rubidium and czsium derivatives which are soluble in absolute methyl and ethyl alcohol.The solu- bility in methyl alcohol is very much greater than in ethyl alcohol. Oxidising agents convert the chloro-tungstites into sexavalent tungsten derivatives. A vigorous reaction takes dace on treatment with potassium cyanide with the production of double cyanides of the type M,W(CN),. The compounds of the type (iii) and (iv) are regarded as derivatives of metatungstous acid 02W*OH -+ Cl4W*OR whilst those of types (i) and (ii) are regarded as deriv- atives of orthotungstous acid W(OR,) + (HO)2W(OH)3 e HFd>WCl,. For the special description and preparation of the individual chloro-tungstites the original should be consulted.J. F. S. Decomposition of Stannous Chloride by Water and by Potassium Hydroxide Solutions. C. M. CARSON (J. A ~ T . Chem. Soc. 1919 41 1969-1977).-Making use of the principles of the phase rule the author has investiqated the action of water and potassium hydroxide on stannous chloride. The1 experimental results show that the compound 2SnC12,7Sn(OH) is the most. basic of all the basic stannous chlorides. A slightly variable crystalline material of approximately the formula 3SnC1,,5Sn0,3H20 is the precipitate commonly formed bv the action of boiling potassium hydroxide on an excess of stannous chloride and there is no corn- pound of intermediate composition. Whether any basic compound lies between 3SnC1,,5Sn0,3H20 and the normal salt was not deter- mined.The precipitates usually formed by t-he action of water on stannous chloride contain such a large proportion of stannic com- pound that the analyses are of no value in ascertaining the composi tion of the basic stannous chlorides. The Peroxides of Bismuth. RICHARD ROBERT LE GEYT WORSLEY and PHILIP WILFRED ROBERTSON (T. 1920 117 A. GUTBIER and 0. MAISCH (Ber. 1919 52 [ B ] 2275-2280).-The experi- J. F. S. 63-67). Behaviour of Hydrogen towards Rhodium.MINERALOQICAL CHEMISTRY. ii. 117 ments were performed in the same manner as with palladium iridium and platinum (A. 1913 ii 608; 1919 ii 367 368). The results may be summarised in the following manner. The deep black modification rhodium-black is able to absorb far more hydrogen than any other form. The maxima of hydrogen absorp- tion amounted to 180 volumes a t 190° for the greyish-black form 165 volumes a t 40° for the slightly greyish-black variety and 206 volumes at Oo for the deep black modification. (The varieties are obtained in the order given by the reduction of sodium rhodium chloride by hydrazine in faintly acid neutral and ammoniacal solu- tion respectively; the purest preparations dried in a vacuum over phosphoric oxide contained about 3% of water and 0.3% of oxygen.) The absorption of hydrogen by rhodium is much less than by palladium and corresponds with that observed with platinum. Spongy rhodium like spongy platinum only absorbs small amounts of hydrogen. H. W.

ISSN:0368-1769    

DOI:10.1039/CA9201805108

出版商:RSC    

年代:1920

数据来源: RSC

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MINERALOQICAL CHEMISTRY. Mineralogical Chemistry. ii. 117 Hausmannite in the Batesville District Arkansas. H. D. MISER and J. G. FAIRCHILD ( J . TT7ashington Acad. Sci. 1920 10 1-8).-The abundant manganese ores of this district consist of the oxides psilomelane hausmannite braunite manganite pyrolusite and wad the first two which occur intimately intergrown being the commonest. They occur as irregular masses weighing from less than a pound to 22 tons embedded in clay limestone shale sandstone etc. The hausmannite however occurs as a replacement material only in the limestone and as a residual material in clay derived from limestone. Analysis I is of a sample from the W. T. Gray mine near Pfeiffer and I1 from Club House mine near Cushman; they correspond with hausmannite (Mn,O,) with 13% and 31% admixed psilomelane respectively.MnO. 0. Fe,O,. AlI.03. SiO,. CaO. I. ...... 91.38 7.78 Nil. Nil. Nil. Trace 11. ...... 90.40 8-87 0*48* 0.10 Trace - MgO. BaO. H,O. Total. Sp. gr. 1. ...... Trace 0-26 0.62 100-04 4.836 II. ...... Trace Nil. 1.03 100.88 4-778 * Fe,O trace. The ' braunite' desoribed by Penrose in 1891 is shown to be such a mixture of hausmannite and psilomelane. Braunite is readily distinguished by the fact that it yields considerable gelatinous silica. L. J. S.ii. 118 ABSTRACTS OF CHEMICAL PAPERS. Analyses of Dolomites. ALBERT R.OTHROCK and J . B. SHunrAKm (Chem. News 1920 120 29-31).-The following analyses of dolo- mite rocks and dolomitic limestones from various localities show considerable variations from typical dolomite CaMg(CO,) which ccntains CaCO 54*35% MgCO 45.65%.I white compact crystal- line from Ossining New York. 11 dark grey massive from Cum- berland. 111 light-coloured massive from Cerro Gordo Inyo Co. California. IV grey compact with conchoidal fracture from Frankenstein Silesia ; this approaches magnesite. V white corn- pact and crystalline resembling marble from near Keeler Cali- fornia. VI greyish-white crumbly and saccharoidal from the Binnenthal Switzerland. VII hard compact from Gerolstein Rhine. VIII light colour with pearly lustre from Costa da Val Tyrol ; 2CaC03,MgC0,,FeC0,. IX greyish-white compact from New Almadin California. X light grey granular and porous from Raible Carinthia. XI. grey large crystals from Brewster’s New York. XII a outer layer of pale pink crystals b inner portion of dark grey crystals.XIII grey from ‘The Dolomites,’ Tyrol. XIV from the Brenner Pass. CaCO,. MgCO,. Fe,O,. Al,03. SiO,. Total. Sp. gr. I. ...... 51-97 37.40 0.20 Trace 10.61 100.18 2-93 11. ...... 57.59 24.98 16-05 0-87 0.56 100.05 2.88 III. ...... 87-88 11.85 0.09 - 0.06 99.88 2.57 V. ...... 66.08 1.15 0.06 - 32-57 99.86 2.7 VII. ...... 52.93 44.33 0.80 0.22 1-23 99-51 2-82 IX. ...... 53-28 45-18 8.57 - 0.4 100.11 ? 2.8 XII~. ...... 56-63 41.37 1-18 0.63 0.23 io0.04 - XII~. ...... 57.18 36-83 0.89 1-16 3-96 100.02 - XIII. ...... 94.21 4.15 0.56 0.57 0.48 99.97 2-73 IV. ...... 27.04 67.91 3.71 0.73 0.13 99.52 2.9 VI. ...... 49-00 40.23 0.48 - 10-84 100.55 2.85 VIII. ...... 49-59 24.50 2.36 - 0.12 100.01* 3.01 X. .,.... 54.64 45-18 Trace 0.28 0.23 100.33 2-7 XI. ...... 59.98 36.83 2.44 - 0.33 99.58 2.9 -+ XIV. ...... 96.25 2-98 0.50 0.35 100.08 - * Including FeC0,,23.44. L. J. S.

ISSN:0368-1769    

DOI:10.1039/CA9201805117

出版商:RSC    

年代:1920

数据来源: RSC

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ii. 118 ABSTRACTS OF CHEMICAL PAPERS. Analytical Chemistry. Application of the Interferometer to Gas Analysis. J. D. EDWARDS (Chtem and M e t . Eng. 1919 21 56&565).-The gas interferometer measures the difference in refractivity of two gases of binary mixtures. Usually one of the components is taken as the standard gas and the difference in refractivity of the mixture and one of ita components is determined. For a change of a% of one of the componenta the change in refraotivity AB = 2731 T p/760 . a/ 100(R - R2).ANALYTICAL CHEMISTRY. ii. 119 Each scale division corresponds with a definit’e value of Ar which is the difference in refraction of the two gases. The calibration of the instrument is described (see also A. 1918 ii 47). I n measuring a small percentage of a gas which deviates appreciably from Boyle’s law a correction is necessitated as the refraotivity of the gas a t a low partial pressure differ8 from the value calculated from the pressure ratios.I n taking readings calibration curves should be drawn for different temperature and pressure intervals from which readings may be taken by interpolation. A variation of 3O in the tempera- tures of estimation and of calibration involves an error of 1%. The error due to shifting of the central white or achromatic fringe was investigated by Adams (A. 1915 ii 478). Typical illustrations are given of t-he use of the instrument for air-carbon dioxide mixtures. It may also be employed for the analysis of flue gases and the determination of helium in mixtures. A table is given showing the relative sensitiveness of the inter- ferometer for different gases. Improved Orsat Apparatus €or Gas Analysis.G. W. JONES and F. R. NEUMEISTER (Chem. and Min. Eng. 1919 21 734-736).-The modification of Orsat’s apparatus used by the Bureau of Mines U.S.A. has a Jager’s copper oxide tube for the removal of hydrogen and carbon monoxide. The gas burette can b4 put in communication either with the Orsat pipettes containing the usual reagents for carbon dioxide unsaturated hydro- carbons and oxygen or with a compensator of the Peters- sen type the mercury i n which forms contact with a platinum wire and lights a lamp when the levelling bulb is raised or lowered and thus facilitates the reading of the level. The copper oxide tube above the Orsat bulbs is heated by means of an electrical heater which is lowered over it and then rests on supports. For the deter- mination of hydrocarbons in a gas a combustion is made in the combustion pipette with a measured quantity of oxygen the pipette being cooled by compressed air to prevent breakage and the amounts of the two predominating hydrocarbons are calculated by means of the usual formula from the total contraction and amount of carbon dioxide found after the combustion.[See further J . SOC. Chem. Ind. 1920 1388.1 Theory of Electrometric Titration. W. D. TREADWELL (Helu. Chim. -4cta 1919 2 672-680).-A theoretical paper in which the determination of the end-point in the titration of silver solutions is considered. The method consists in measuring the ter- minal voltage between a standard silver chloride cell and a silver eleotrode immersed in the solution the end-point being that at whioh the voltage becomes zero.The theory is considered for the titration of solutions of pure silver salts and of the case where there is a quantity of other substances present. Electrometric Titration. W. I,. TREADWELL and L. WEISS (Helv. Ch,im. Actu 1919 2 680-697).-1t is shown that the end- W. J. W. C . A. M. J. F. S.ii. 120 ABSTRACTS OF CHEMICAL PAPERS. point of many titrations may be determined electrometrically by measuring the terminal voltage between a metal electrode whiqh is immersed in the solution being titrated and is capable of sending the same ions into the solution and a comparison electrode made of the same metal and the insoluble precipitate or product produced in the titration.The two terminals arG direct,ly connected with a voltmeter and the point of zero potential is the end-point of the titration that is the point at which the concentration of the metal ions is the same in both the solution being titrated and the comparison electrode. It is essential that during the titration the liquid should be rapidly stirred and the authors describe an appara- tus in which the comparison electrode is built up in the stirrer. I n t.he case of silver solutions the comparison electrode is Ag I AgC1. sat.[\ a silver wire furnishes the electrode in the solution and the titration is carried out with standard sodium chloride. The results are extraordinarily good. I n the presence of foreign sub- stances t.he titration values are too low but they may be corrected from the course of the titration curve. Hydrogen sulphide may be titrated with silver ions using as comparison eleotrode the combina- tion Ag I Ag,S.dil. NaN0,II. Mercurous ions may be titrated by chloride ions using as comparison electrode Pt . Ag I Hg2C1 dil. H2S04(( and a similar silver-plated platinum wire as titration electrode. Better results are obtained if the titration is carried out with bromide ions and the calomel in the comparison electrode substi- tuted by mercurous bromide. Copper ions may be titrated by ammonium thiocyanate using as comparison electrode Cu 1 CuCNS . dil. NaHSO 11. In the foregoing cases soluble electrodes have been employed; further experiments were made with insoluble electrodes and it is found that zinc ions may be titrated with ferrocyanide ion using as titration electrode a platinum gauze and as comparison electrode Pt I Zn,Fe(CN)6.HCl(5 C.C. in 300H20)II. The titration in this case is carried out a t 70°. Ferrous chloride may be titrated with potass- ium dichromate using an already completed titration as the com- parison electrode and platinum wires in both solutions. This titra- tion is also carried out in warm solutions. Uranous ions may be titrated with potassium permanganate in warm solution using platinum wires and a uranyl solution as the comparison electrode. Vanadyl solutions may be similarly titrated with permanganate using platinum wires and a vanadate solution as comparison eleo- trode. I n the case of the hydrogen-ion titration the electrode is too slow in its action for the method as at present constituted to give sharp results. Electrometric Titration.J. PINKHOF (Chem. Weekblad 1919 16 1163-11 67) .-The investigation concerned the selection of a constant electrode which should have the same potential as the electrode of the liquid at. the moment when the end-point was reached. It would then be merely necessary to determine whether the difference of potent,ial of the two electrodes was positive or nega- J. F. S.ANALYTICAL CHEMISTRY. ii. 121 tive. To ascertain which compensation electrode is suitable a poten- tial measurement was made during titration and when the desired potential was found a combination of electrode and liquid was sought which would give this potential.For the titration of halogens in presence of each other N-potassium bromide is suitable for the com- pensation electrode in the estimation of the iodine. For the bromine Ag-AgCl-O*2NCl. is used. I n titrating heavy metals with sodium sulphide a silver-halogen compensation electrode is employed. Titrations of bases with mercuric oxide electrode and the use of the hydrogen electrode are discussed. W. J. W. A Rapid Hydrogen Electrode Method for Determination of Hydrogen-ion Concentrations in Bacterial Cultures or in other Turbid or Coloured Fluids. HARRY M. JONES (J. Znfect. Dzs. 1919 25 262-268).-As compared with the colori- metric method the apparatus described has wider application is more accurate less cumbersome and only slightly less rapid.The hydrogen electrode vessel described was designed to provide a vessel accurate a t least to 0.01 p and to give a rapid saturation with hydrogen gas and yet one which is easily construct-ed. A rapid and labour-saving technique combining the indicator and the gas-chain methods is described which obviates the difficult task of preparing standard solution for the former method and of making needless repetitions by the latter. CHEMICAL ABSTRACTS. Iodometric Estimation of Acids. I. M. KOLTHOFF (Pharm. Weekblad 1920 57 53-68).-The author has investigated the iodometric method especially with reference to weak acids. The influence of dilution in the case of strong acids of catalysts and of a variation in the amount of potassium iodide added was deter- mined. Tests were carried out with hydrogen chloride tartaric acid citric acid lactic acid malic acid succinic acid acetic acid formic acid benzoic acid salicylic acid sodium phosphate and currant juice.The iodometric method givm exce,llent results with strong acids especially if diluted in which case the reagents after mixing must remain for ten minutes before titration. A deficiency of potassium iodide causes inaocuracy. Organic oxy-acids can be accu- rately estimated if a salt of calcium magnesium or zinc is added. For phosphoric acid and weak organic acids not containing a hydroxy-group the method is unsuitable but i t may be used in the case of formic acid. The applicability of the method to the estima- tion of fruit juices requires further investigation. W. J. W. Indirect Electrolytic Estimation of Anions without Platinum Electrodes.11. E. LASALA (Anal. Fis. Quim. 1919 J7 235-247).-A continuation of work already published (A. 1919 ii 239). The present communication deals also with anions which form insoluble silver salts. These are carbonate oxalate ferro- and ferri-cryanide orthophosphate arsenate chromate and thiocyanate. The anion is precipitated as insoluble silver salt.ii. 122 ABSTRACTS OF CHEMICAL PAPERS. This is dissolved in a suitable solvent and the silver estimated elec- trolytically with a nickel-plated copper cathode and an iron anode. Satisfactory results were obtained only in the case of carbonate oxalate ferro- and ferri-cyanide and thiocyanate. The method was applied to the separation of chloride and iodide. The precipitated mixed silver haloid is washed with ammonia solution (D 0.92). The silver chloride is electrolysed after the addition of ammonium sul- phate. The residual iodide is dissolved in 20% solution of potassiu-m cyanide and electrolysed.A small correction must be applied for the solubility of silver iodide in ammonia solution. W. S. M. Electrolytic Estimation of the Halogens. An Indirect Method. J. H. REEDY (J. Arner. Chem. Soc. 1919 41 1898-1902). -The decomposition voltage of .A7-sulphuric acid saturated with silver chloride between silver coated with silver chloride as anode and bright platinum it9 cathode is found to be 0.59 volt which corresponds exactly with the sum of the solution potential of silver ((3.52 volt) and the overvoltage of hydrogen on bright platinum (0.07 volt).As long as this limiting voltage of 0.59 volt is not exceeded the electrolysis of haloid solutions with silver anodes proceeds with the formation of an adherent layer of silver haloid o n the anode without precipitation in the solution. With the com- pletion of the deposition of the halogen silver ions appear in the solution with no break in the continuity of the current and with scarcely any rise in potential. An indirect method of estimation of chlorides bromides and iodides is based on the above facts. The principle of the method consists in depositing the halogen on a silver anode under a constant voltage of 0.59 volt; some silver will thereby be lost from the anode. The anode is then dried and weighed and the silver haloid is reduced to metallic silver and the loss in weight determined which gives the weight of the halogen. A lead accumu- lator of large capacity is connected across the ends of a sliding rheo- stat and a current of E.M.P.0.59 volt tapped off. The electrolysis vessel consists of a beaker of 400 C.C. capacity fitted with an anode of silver gauze coated with silver electrolytically and a bright platinum cathode and a stirrer. The electrolysis is carried out with 200 C.C. of solution for about fifteen minutes; the current flowing at first is rather large but after about fifteen minutes it becomes negligible. The potential is then raised to 0.60 volt for five minutes. The silver electrode with its halogen deposit is washed dried and weighed. After weighing it is made the cathode in a dilute solu- tion of sodium hydroxide and electrolysis carried out until hydrogen is freely liberated from the surface.The silver haloid is thus reduced t o black silver which is not very adherent and must be carefully handled. After a thorough washing the electrode is heated at 500° in an electric furnace until the deposit is white and thoroughly sintered together. It is then weighed and the loss in weight gives the weight of the halogen. The results given in the paper show that hhe method .i,s qlaibe as good as the usual gravimetric method. J. F. S.ANALYTICAL CHEMISTRY. ii. 123 Estimation of Bromide in Mineral Waters and Brines. W. W. SKINNER and W. F. BAUGHMAN (Science 1919 50 50).- Chromic acid in concentrated solution liberates bromine quantita- tively from bromides a t the ordinary temperature and the bromine is removed by aspiration.Only a trace of chlorine is liberated from chlorides. When chromic acid acts on a solution containing chloride and bromide therefore the mixture of halogens removed by aspira- tion is dissolved in a solution of sodium sulphite and hydroxide which is then evaporated to dryness and the residue again treated with chromic acid solution and aspirated a second time. The double treatment gives very trustworthy results. CHEMICAL ABSTRACTS. Estimation of Alkali Sulphide in Dilute Solution. H. G . BENNETT and W. G. BENNETT ( J . SOC. Leather Trades Chem. 1919 3 ( l l ) 190-193).-A measured quantity of the solution contain- ing not more than 0'04% of hydrogen sulphide is distilled in an atmosphere of carbon dioxide with an excess of boiling magnesiuni chloride solution.A current of carbon dioxide carries the liberated hydrogen sulphide into a receiver containing standard iodine solu- tion. A second receiver containing standard sodium arsenite solu- tion is arranged to trap any iodine vapour carried over by the gas. The method is accurate under these conditions and provided there are no rubber connections exposed to the iodine vapour. D. W. Neutralisation Curve of Sulphurous Acid. I. M. KOLTHOFF (Chem. Weekblad 1919 16 1154-1163).-The accuracy of the results when sulphurous acid is titrated with methyl-orange or dimethyl-yellow a3 indicator depends on the concentration of the hydrogen ions of the sodium hydrogen sulphite and therefore also on the second dissociation constant of the sulphurous acid.This has been determined from the degree of hydrolysis of solutions of sodium sulphite and found to be 1 x 10-7 at 15O. The hydrogen-ions con- centration of a 0.1 mol. sodium hydrogen sulphite solution calculated from the two dissociation constants gave the value [H*]=3*3 x A curve showing the neutralisation of sulphurous acid was con- structed. I n $he titration of sulphurous acid errors of +_2% and of * 6% were obtained when the indicators were dimethyl-yellow and phenolphthalein respectively. The addition of sodium chloride reduced the error with phenolpht.halein to *2%. Accuracy can only bo ensured if excess of barium nitrate is added after the pink coloration of the phenolphthalein has appeared and the titration then continued to the end-point. Estimation of Sulphates in the presence of Organic Sulphonic Acids.T. CALLAN JAS. A. RUSSELL HENDERRON and R. BARTON ( J . SOC. Chenz. lnd. 1919,38 410-411~).-The solution of the substance (containing about 0.2 gram of sulphate) is rendered slightly ammoniacal (a small quantity of calcium chloride is also added to precipitate any carbonate which is then separated by filtration) and the mixture is boiled until all excess of aniinonia W. J. W.ii. 124 ABSTRACTS OF CHEMICAL PAPERS. has been expelled. Twenty C.O. of Nlkbarium chloride solution are then added the heating continued for a few minutes and the excess of barium titrated with W / 4-potassium chromate solution using starch-iodide paper as indicator.A drop of the mixture is placed on the paper and the edge of the spot is touched with a drop of very dilute hydrochloric acid. A blue colour develops in about ten seconds when an excess of soluble chromate is present. An immediate blue colour indicates that a considerable excess of chromate has been added. w. P. s. Detection of Nitrogen in Organic Compounds by Castellana’s Reaction. J. FLIERINGA (Pharm. WeekbEad 1920 57 3-4).-Castellana’s reaction (A. 1905 ii 207) may give a positive reaction even in nitrogen-free compounds owing t o com- bination of atmospheric nitrogen if the magnesium is in excess. It is preferable to use a mixture of 2 parts of sodium carbonate and 1 part of magnesium. Sodium carbonate containing 1 molecule of H,O should be employed. Addition of sugar to the reaction mixture eliminates the error caused by absorption of atmospheric nitrogen.W. J. W. The Relative Accuracy of Colorimetric and Titrimetric Procedures for estimating Nitrogen as Ammonia. E. R. ALLEN and B. S. DAVISSON ( J . Bid. Chem. 1919 40 183-197).- It appears that the colorimetric methods are slightly the more accurate. On the other hand the conditions for accurate titrations may be attained more easily than those for satisfactory Nessler esti- mations and at the same time the titrimetric methods are applic- able t o a wide range of nitrogen values. The chief disadvantage of the Nessler process ia the fact that the reaction is imperfectly understood and the appearance of clouds and precipitates difficult to avoid. Again it is believed that the personal error is greater in colorimetric methods than in titrimetric methods.The general conclusion is therefore in favour of the titrimetric methods. J. C. D. Estimation of Nitrogen in Nitrates. F. PILZ (Zeitsch Eandw. Vers.-Wesen Deutschosterr. 1919 22 180-188 ; from Chem. Zentr. 1919 iv 767).-Comparative estimations of nitrogen in nitrates by various methods showed that reduction with Devarda’s alloy yielded the most trustworthy results and is to be recommended more than the method described by Arnd (A. 1917 ii 504). Busch’s method (A 1905 ii 418j is less trustworthy. Other methods investigated were the one proposed by Ulsch (reduc- tion in acid solution with iron powder) and the indirect method Method for the Estimation of Minute Quantities of Nitrogen in Organic Substances which furnishes a New Quantitative Method of Diagnosis in some cases of Mental Disease.R. V. STANFORD (Rep. Chem. Lab. Card@ C i t y Mental Hospt. 1919 No. 2. Compare A. 1913 i 93i)).-A small quantity (conversion of the nitrate into chloride). w. P. s.ANALYTICAL CHEMISTRY. ii. 125 of the organic substance as for example 1 C.C. of cerebrospinal fluid is oxidised by the Kjeldahl process in the usual manner. The subsequent distillation is carried out in the ordinary apparatus but the distillate is collected in three fractions in Nessler cylinders. The third fraction should show little or no coloration with Nessler’s reagent. The colour produced by the first two fractions is com- pared in the usual manner with that produced by a standard solu- tion of ammonium chloride.Considerable a r e has t o be taken to avoid errors arising from ammonia in the reagents and apparatus. The author records a number of analyses of cerebrospinal fluid from mental cases. The ‘ I nitrogen number,” that is the number of hundredt.hs of a milligram of total nitrogen contained in 1 C.C. of cerebrospinal fluid may be of value in diagnosis. On the whole density and nitrogen number of the fluids run parallel to one an0 ther . No traces of choline and only the merest traces of ammonium salt were detected in the cerebrospinal fluid in mental disease. J. C. D. Procesa for the Estimation of Arsenic. Chemistry of the Marsh-Berzelius Process. B. S. EVANS (Analyst 1920 45 8-17).-The arsenic is evolved as hydrogen arsenide in the same way as in the ordinary Marsh-Berzelius test but is conducted over a roll of red-hot copper which retains the arsenic the amount of which is obtained from the increased weight of the copper.The compound formed with the copper usually melts and resembles solder in appearance but occasionally brilliant silvery-white blade- shaped crystals are produced. Analyses of the deposits gave 67.5 and 70.5% of copper and 32.28 and 29.27% of arsenic and thus appeared to be mixtures of the arsenides Cu,As and Cu,As,. The resulk obtained with elementary arsenic and various arsenic com- pounds were invariably 1.4% too low and the cause of this loss could not be definitely traced although the rwults indicated that if the arsenic remained in the flask it was in the form of a very stable complex. I n order to prevent separation of elementary arsenic it is advisable that the amount of substance introduced should contain considerably less than 0.5 gram of arsenic.[Sw also J . SOC. Chem. Ind. 1920 February.] C. A. M. Estimation of Arsenic in Tin and Tinnings. LUCIEN VALLERY (Compt. rend. 1919 169 1400-1402) .-Marsh’s method is liable to give results which may ia some cases be wrong to the extent of 75% of the amount found when applied to the estimation of arsenic in tin. The author recommends that the arsenic should be distilled off its arsenic chloride by Hollard and Bertiaux’s method and the arsenic estimated colorirnetrically in the distillate after reduction to colloidal arsenic by means of hypophosphorous acid. In this way the results obtained are accurate to within 3% of the total a t a concentration of 1 in 100,000.W. G.ii. 126 ABSTRACTS OF CHEMICAL PAPERS. New Methodof Estimation of Carbon and Hydrogen in Organic Substances. KUNIHIKO SUMIKURA (J. Tokyo Chem. SOC. 1919 40 593-606).-The essential point of the method is the combined use of platinum and cerium dioxide. (1) Substances containing Carbom Hydrogen (and Oxygen) only.-An ordinary combustion tube is filled in order with cerium dioxide (5 cm.) porcelain boat cerium dioxide (8 cm.) (only one burner is necessary under each of these) and a coil of platinum or platinum-iridium wire (2 m.) which is electrically heated with adjustable resisb ances. The wire is first heated in a separate tube before being placed in the combustion tube.The cerium dioxide is prepared by heating copper gauze packed with asbestos soaked in a solution of ceric nitrate. (2) Substances containing Nitrogen and Sulphur.-Lead dioxide is placed between the second cerium dioxide gauze and the platinum coil and is heated a t 300-350O. (3) Substances containing Halogens.-Silver foil is placed between the second cerium dioxide gauze and the platinum wire. I f nitrogen is also present lead dioxide is placed between the silver foil and the platinum wire and is heated a t 300-320O. (4) Substances containing Phosphorus.- Lead monoxide is mixed with the substance. Trustworthy results are recorded. CHEMICAL ABSTRACTS. Rapid Estimat.ion of Carbon Monoxide in Air. ARTHUR B. LAMB and ALFRED T. LARSON (J. Amer. Chem. SOC. 1919 411 1908-1920).-Two methods for the rapid estimation of small quantit,ies of carbon monoxide in air are described.I n the first method the gas is passed over a platinum wire heated to redness and the carbon monoxide partly burned in contact with it. The gas then passes over heated copper oxide where the carbon mon- oxide is completely burnt; i t then passes through a spiral con- tained in a thermostat to bring it to its original temperature and finally over a second exactly similar platinum wire heated by the same current as the first. The two platinum wires are made arms of a Wheatstone bridge and since the first wire will necessarily be hotter than the second they will have different resistances. The change in the resistance of the first wire gives a measure of the carbon monoxide concentration.I n the second method the mix- ture is passed through a platinised platinum catalyst when the carbon monoxide is completely burnt. The temperature change is measured by a thermo-element and indicates the concentration of carbon monoxide. Both methods are rapid and the latter is par- ticularly accurate easy to instal and to operate. The catalyst with reasonable precautions remains active for many weeks. J. F. S . Apparatus for the Volumetric Estimation of Small Quantities of Carbon Dioxide by Displacement from Liquids by means of a Rapid Current of Air at the Ordinary Tem- perature and Pressure. A. COSTANTINO (Atti R. Accad. Lincei 1919 [v] 28 ii 118-121).-1n the apparatus described whichANALYTICAL CHEMISTRY. ii. 127 consists of a closed system a rotary mineral oil pump causes the repeated circulation of purified air first through the liquid con- taining the carbon dioxide and then through a definite volume of standard barium hydroxide solution this being subsequently titrated with acid in presence of phenolphthalein.The determin- ation occupies in all about forty-five minutes. Test experiments with sodium carbonate solutions cont9aining 6-4-21 mg. of carbon dioxide show that the method yields accurate results. T. H. P. Eetimation of Metals by Electrolytic Deposition without using an External Supply of Electricity. MAURICE FRANCOIS (Ann. Chtim. 1919 [ix] 12 178-192).-A more detailed account of work already published (see A. 1919 ii 34). W. G. Use of Nickel Crucibles for the J.Lawrence Smith Method in Estimating Soil Potassium. SETH 5. WALKER (J. Ind. Eng. Chem,. 1919 11 1139-1140).-The same results are obtained whether platinum or nickel crucibles are used for the heating of the soil with ammonium chloride and calcium carbonate but the nickel crucible is attacked by the mixture and the life of the crucible is short,. w. P. s. The McCrudden Gravimetric Calcium Method Modified. J. P. HALVERSON and J. A. SCHULZ ( J . I n d . Enq. Chem. 1920 12 77-78).-The calcium oxalate precipit.ate is collected on a filter of specially prepared asbestos contained in a Gooch crucible; after washing both filter and precipitate are mixed with water acidified with sulphuric acid and titrated a t 65O with perman- ganate solution. The filter is prepared by digesting ignited asbestos with dilute sulphuric acid and a slight excess of per- manpanate for one hour at 60° to 70°.and then washinp it until freeofrom acid. [See further .7. Soc. (7htem. Ind. 1920 Fkbruary.] w. P. s. Estimation of the Calcium Oxide Content of Milk of Lime. GEORG LENART (Zeitsch. Ver.. deut. Zuckem'nd. 1919 1-15 360-361) .-MategEek's table (0sterr.-Ungar. Zeitsch. Zuckerind. 1871 12 718) correlating the sp. gr. and calcium oxide content of milk of lime is regarded as far from correct whilst that published by Lunge and Blattner (Dingl. Polytechn. J. 1883 466) is also considered to be untrustworthy. Experiments are described demon- strating the difficulty of obtaining exactt results by means of the hydrometer (the method of density determination adopted in the construction of the second table) since the readings are influenced by the shape and length of the spindle by the width and depth of the column of liquid in the cylinder and also by the degree of movement imparted to the liquid a t the moment of observation.Using a pyknometer consisting simply of a cylindrical vessel having a capacity of about 500 c.c. provided with a ground-glass plate as cover a new table has been constructed by the author in which the density values range from 1.0085 to 1.2195 ( 1 - 5 O to 26.2' Be'.)ii. 128 ABSTRACTS OF CHEMICAL PAPERS. at 20° temperature corrections being stated for readings made between 20° and 40°. Milk of lime which has been vigorously shaken for about two hours assumes a viscous condition in which the particles remain almost completely in suspension for some days this being believed t.0 be due to the formation of a hydrated Compound probably Ca( OH),,H,O to which attention has already been directed by Herzfeld (Zeitsch.Ver. deut. Zuckerind. 1897 817) and by Karcz (Chem. Zeit. 1898 22 38). The Permanganate Method for Copper. LOUIS F. CLARK (2. Ind. Eng. Chem. 1919 11 1138-1139).-A modification of the procedure for the titration of cuprous thiocyanate with per- manganate solution is proposed with the object of making the estimation less arbitrary. The cuprous thiocyanate precipitate is treated in a beaker with 25 C.C. of hot 4% sodium hydroxide solu- tion until the precipitate is decomposed 25 C.C. of cold 15% sulphuric acid and a quantity of 1% ferric sulphate (anhydrous salt-) solution are added and the mixture is titrated with permanganate solution.Towards the end of the titration and when the mixture becomes whiter in d o u r 5 C.C. of concentrated hydrochloric acid are added and the titration then complet.ed. Under these con- ditions 6 atoms of copper should be equivalent t o 7 atoms of iron or a ratio factor of 0.1626; the ratio factor actually found as the result of experiment is 0.1646. [See further J . SOC. Chem. Znd. Microchemical Identification of Soluble and Insoluble Mercury Compounds. G. DENIGBS (Bull. SOC. Pharm. Bordeaux 1919; from ,4nn. Chim. anal. 1919 rii1 1 383-385).-The tests depend on the characteristic crystals obtained when a small quantity of the compound is treated with a drop of potassium bromide iodide solution.Mercurous compounds and mercuric cyanide are oxidised previously with bromine. Mercuric iodide itself is identified by the crystals obtained from its alcohol or acetone solution. w. P. s. OTTO SASSE (Pharm. Zeit. 1919 64 633).-Referring to the method described by Utz (A. 1919 ii 428) the author mentions that he himself had published a method (Pharm. Zeit. 1887) for the volumetric estimation of mercuric chloride; this method depends on a tiha- tion with potassium iodide solution and is trustworthy. J. P. 0. 1920 138~.] w. P. s. Volumetric Estimation of Mercuric Chloride. w. P. s. Application of Rotating Reductors in the Estimation of Iron. WALTER SCOTT ( J . Ind. Eng. Chem. 1919 11 1135-1137). -Gooch and the author have shown previously (A.1918 ii 373) that vanadic acid may be reduced by rapidly rotating anodes of silver or copper and the author now describes a similar method of reduction for ferric salts. The latter in sulphuric acid solution are reduced completely by rotat,ing reductors of zinc or aluminium with or without the use of an external current. w. P. s,ANALYTICAL CHEMISTRY. ii. 129 A Sensitive Reaction for Manganese. P. H. HERMANS (Pharm. WeekbEad 1919 56 1344-1346).-Caron and Raquet's reaction for manganese (RLp. Pharm. 1919 97) was independently discovered by the author and was in addition utilised as a test for nitrogen tetroxide and for nitrites. All oxidising agents are not effective in promoting the red coloration for example hydrogen peroxide potassium persulphat e chlorine bromine iodine chloric acid iodic acid potassium ferricyanide but addition to them of 0.5% solution of osmic acid produces a satisfactory result.Active oxidising agents for the test are bleaching powder potassium per- manganate and dichromate lead peroxide cerium ammonium nitrate nitrous acid and nitrogen tetroxide. The reaction is sensitive to 0.07 mg. manganese or 0.03 mg. sodium nitrite per C.C. of solut,ion. The red coloration is considered to be a complex alkali manganese oxalate. W. J. W. Lead peroxide is most suitable for the manganese test. Indirect Detection of Tin. FR. FEIGL (Chem. Zeit. 1919 43 861).-Ferrous salts give a red precipitate with an ammoniacal solution of dimethylglyoxime but the presence of ferric salts which give a precipitate of ferric hydroxide with the reagent interferes with the test.The precipitation of ferric iron as hydroxide and of ferrous iron as ferrous dimethylglyoxime may be prevented by adding an organic hydroxylated compound. such as citric or tart.aric acids or potassium sodium tartrate and the ferrous ion then gives a carminered solution. I n each case complex iron compounds are formed. I n usinq this reaction as a sensitive indirect test for tin the mixed sulphides mesumably of antimony and tin are dissolved in hydrochloric acid and one portion of the solution is tested for antimony with iron wire. I n a second portion the tin and anti- mony are precipitated by means of pure zinc and the tin extraded from the deposit by means of concentrated hydrochloric acid. The solution is poured into a hot dilute solution of ferric chloride.a little citric acid or potassium sodium tartrate added and the liquid tested with ammoniacal alcoholic dimethylglyoxime solution. The ferrous ion formed by reduction with the stannous ion will give a red coloration. the intensity of which is proportional t'o the amount of stannous chloride. C. A. M. Estimation of Thiophen in Industrial Benzenes. ANDR& MEYER (Compt. rend. 1919 169 1402-1404).-A modification of DenigBs's method (compare A. 1895 ii 332 372). Denig'es's reagent is prepared by dissolving 50 grams of mercuric oxide in 200 C.C. of sulphuric acid diluted with 1000 C.C. of water. Twenty C.C. of this reagent are mixed with 75 C.C. of methyl alcohol and 5 C.C. of the benzene under examination in a stoppered bottle.The mixture is shaken from time t o time and after t.hirty minutes is filtered. Ten C.C. of the filtrate are diluted with 20 C.C. of water a few drops of nitric acid are added and the whole is titrated withii. 130 ABSTRACTS OF CHEMICAL PAPERS. iV/10-ammonium thiocyanate solution using 1 C.C. of a 20% iron ammonium alum solution as indicator. I n view of the possible presence of acetone in the methyl alcohol a blank experiment is conducted using pure benzene free from thiophen. The difference between the two titrat,ions is a measure of the mercury precipit.ated by the thiophen as the compound (HgO),SO,,HgSC,H and the factor for the conversion of mercury to thiophen is 0.14. W. G. Titration and Partial Reduction of Nitro-compounds with Titanous Chloride.C. F. VAN DUIN (Chem. TVeekbZad. 1919 16 1111-llZZ).-An examination of the titanous chloride method for the titration of nitro-compounds. The constancy of titre of a titanous chloride solution at the ordinary temperatures and after helating was especilally investigated ; also the general applicability of the method to various classes of nitro-compounds. A t the ordinary temperatures only slight variations in titre were found after keeping for several days. Titration experiments before and after heating the titanous chloride solution were carried out in comparable conditions in presence of alcohol hydrwhlorio acid and acetic acid. It was found that tqhe assumption of an invariable titre during the heating of the titanous chloride solution led to quite erroneous results.The error is small in presence of acids especially in hydrochloric acid tderabb results being only obtained in strongly acid solutions. From experiments wit.h picric acid mdinitrobenzene and s-trinitrotoluene the author concludes that the method yields results of the same order of accuracy as t(he Dumas method. The reduction and titration of the following classes of nitrecompounds were carried out nitroamines (s-trinitro- phenylmet#hylnitroamine aminotrinitrophenylmethylnitroamine trinitromethylnitroaminophenol trinitromethylnitroaminoanisole trinitrodimetqhyldinitroaminobenzene) tetranitro-compounds (tetra- nitrophenol tetranitrophenylmethylnitroamine tetranitroaniline) and hexanitro-compounds with two nuclei (hexanitrodiphenyl sulphide hexanitrodiphenylsulphone) .I n the reduction of nitro- amines side reactions may take place in which the nitroamino-group is entirely removed from the nucleus. I n all cases blank experi- ments must be carried out in order to estimate the alteration in t-he titanous chloride solution on heating. The amount of excess of the solution necessary for complete reduction must also be deter- mined in each case. Only in those conditions can this method of nitrogen analysis be considered superior to that of Dumas. W. S . M. Detection of Methyl Alcohol in Ethyl Alcohol. M. POLINSKI (Chem,. AnaZ?yst 1919 28 ll).-Five C.C. of the sample are dis- tilled with 50 c . ~ . of water and 3 grams of sodium persulphate the distillate being collected in fractions of 2 C.C. each. The fifth fraction is treated with eight drops of a freshly prepared filtered 1% solut.ion of phenylhydrazine hydrochloride four drops of 5%ANALYTICAL CHEMISTRY. ii.131 potassium f errooyanide and 1 c. c. of concentrated hydrochloric acid. A pink coloration is produced if met,hyl alcohol is present. CHEMICAL ABSTRACTS. Complex Organic Mercury Compounds. EINAR BIILMANN (Medd. K . Vetenskupsukad. Nobel-Inst. 1919 5 No. 12 1-11). -The complex compound formed from allyl alcohol and mercuric acetate is very stable the concentration of the mercuric ion in a 1/160-molar solution being only 10-8-40 (compare A. 1917 i 123). This fact can be made use of in the electrometric estimation of allyl alcohol. The aqueous solution of allyl alcohol is put in a beaker containing mercury which forms one electrode the other being a calomel electrode.A standard solution of mercuric acetate is then run in and the E.M.F. curve plotted. The point of inflexion on the curve is very sharp and accurate results are obtained. Ally1 alcohol can also be estimated by adding mercuric acetate and potassium bromide to the solution and titrating the acetic acid set free with phendphthalein as indicator. The liberation of acetic acid is quantitative according to the equations C3H,-OH + Hg(OAc),= C,H,.O-Hg*OAc+ AcOH ; C,H,*O*Hg*OAc + KBr = C,H,*O*HgBr + OAcK. Mercury can also be estimated very accurately by making use of t-he quantitative reaction C,H,*O*Hg*OH + KBr = C,H,*O*HgBr + KOH. A weighed quantity of mercuric oxide is dissolved in 5N-sulphuric or nitric acid; the solution is diluted with water free from carbon dioxide a few C.C.of allyl alcohol added and then N/5-sodium hydroxide until the liquid is alkaline t~ phenolphthalein. The whole is then exactly neutralised with N/5-sulphuric acid 5 grams of potassium bromide added and the liquid well shaken to give a solution the entrance of carbon dioxide being carefully excluded. The liberated alkali is then titrated. Halogen acids must not be present in estimations according to this method. Maleic and crotonic acids do not give sufficiently stable complexes for estimation by the above methods but allocinnamic acid gives good remlts with the mercuric acetate-potassium bromide method. Cinnamic acid also gives mercury complexes and is to be reported on later. Mercury can be readily and accurately estimated by a modifi- cation of fncze’s method (A.1917 ii 327). To the solution of the mercuric salt or of mercuric oxide in nitric or sulphuric acid is added a large excess of alkali; the whole is then exactly neutralised with standard acid using phenolphthalein it9 indicator. Potassium iodide (5 grams) is then added and the liberated alkali carefully titrated carbon dioxide being excluded. D. D. VAN SLYKE and W. W. PALMER (Proc. Soc. Exp. Biol. Med. 1919 16 140-141). -Carbonates and phosphates are removeld by adding 2 grams of calcium hydroxide to 100 C.C. of urine and filterin after ten minutes. The acidity of 213 C.C. of the filtrate is broug fl t t o pH=8 T. S. P. Titration of Organic Acids in Urine.fi. 132 ABSTRACTS OF CHEMICAL PAPERS.(circa) by adding O.2N-hydrochloric acid until the pink colour of phenolphthalein disappears 5 C.C. of 0.02% Tropceolin 00 are added and the solution is titrated to pH=2-7 with 0-2N-hydre chloric acid the volume being brought. to approximately 50 C.C. by the addition of water towards the end of the titration. The colour is compared with that of 50 C.C. of a control solution with the same pE value and indicator. The amount of 0-2N-hydro- chloric acid required to give the end-point with a control in which water replaces urine is subtracted. The titration est-imates from 93% to 100% of each of the organic acids known to be present in urine in quantitatively significant amounts. It also includes very weak bases but of this class of substance8 only creatine and .creatinine which are estimated to nearly loo% are significant.The titration figure corrected for the amounts of these two bases represenb the organic acids in urine. Detection of P-Hydroxybutyric Acid Acetoacetic Acid and Acetone in Urine. R. LILLIG (Pharm. Zeit. 1919 64 696-697 707-709).-A collect.ion of some sixty methods which have been proposed for the purpose; a brief description is given of each method. w. P. s. Bellier’s Reaction for Vegetable Oils A. VAN RAALTE (Chem. Weekblad 1919 16 969-960).-The benzene used for this reagent must be free from thiophen otherwise a dirty green instead of a violet coloration is obtained. Relative Sensitiveness of the Fehling Phenylhydraziae and Nylander Tests for the Detection ot Dextrose in Urine. GEORGE E.GWE (Amer. J . Pharm. 1919 91 717-719).-Fehling’s test is the most sensitive of the three tests investigated; it yields a reaction with a solution containing 0.00125% of dextrose. The phenylhydrazine test is also sensitive giving a reaction after two hours with a 0.0025% solution of dextrose but the Nylander reagent (potassium sodium tartrate 4 grams; 10% sodium hydroxide solu- tion 100 c.c.; bismuth subnitrate 2 grams) fails to give a reaction unless the solution contains at. least 0.5% of dextrose. E. SCHOWALTER (Zeitsch.LATarhr. Gmusm. 1919 38 221-227).-A reply to Rupp and Lehmann (A.) 1919 ii 434); the author maintains the correctness of his former remarks The Isaacson Method for Estimating Dextroee. ELISABETTA C. PENNELL (J. Lab. Clin. Med. 1919 4 736-737).-Isaacson’s method (A.1918 ii 246) was found highly untrustworthy when compared with the Fehling volumetric method. CHEMICAL ABSTRACTS. W. J. W. W. P. S. Titration of Sugars. (A. 1919 ii 172). W. P. s. CHEMICAL ABSTRACTS. Separation of Dextrose and Lavulose. FRANZ LUCIUS ( Z e i t s c h . iVahr. Genwsm. 1919 38 177-185).-A method for the estimation of dextrose in the presence of lzevulose depends on the fact that the rotation of the latter is destroyed by heating for sevenANALYTICAL CHEMISTRY. ii. 133 hours with dilute hydrochloric acid whilst that of dextrose is not affected. Fifty C.C. of the sugar solution (containing from 2 to 4% of the sugars are mixed with 10 C.C. of 5N-hydrochloric acid and heated in a b oiling water-bath for seven hours. The mixture is then nearly neutralised with sodium hydroxide solution diluted to 100 c.c.treated with animal charcoal and filtered if necessary and polarised at 20°. About 99% of the dextrose actually present is found. The dextrose remaining after the acid treatment cannot be estimated by determining the copper-reducing power of the solution as the lzvulose is converted into reducing substances which how- Separation of ‘ Saccharin ” from Benzoic Acid. E. SCHOWALTER (Zeitsch. Nahr. Genussm. 1919 38 185-194).-The presence of “ saccharin ’’ interferes with the estimation of benzoic acid in foods etc. by the methods described by Mohler von der Heide and Grossfeld (A. 1908 ii 906; 1910 ii 359; 1915 ii 848) but the two substances may be separated from one another by taking advantage of the insolubility of ‘ I saccharin ” in carbon tetra- chloride.The residue obtained on evaporating the et-hereal solu- tion of the two substances a t a low temperature is dried under reduced pressure to remove the last traces of ether and acetic acid and is then treated with carbon tetrachloride; the benzoic acid dis- solved by this solvent may be estimated by titration and the insoluble “ saccharin ” identified by Klostermann and Scholta’s reac- tion (A. 1916 ii 586). Separation of the two substances between sublimation is untrustworthy ; “ saccharin ” begins to sublime a t 120° and 130O. Animal charcoal absorbs considerable quantities of ‘‘ saccharin,” its anhydride and sodium salt as well as benzoic acid Estimation of p-Phenylenediamine. T. CALLAN and JAS.A RUSSELL HENDERSON ( J . Soc. Chem. Id. 1919 38 408-410~).- A modification of a method described by Effront (A. 1905 ii 60) is recommended. Fifty C.C. of sodium hypochlorite solution con- taining 12-15% of available chlorine are diluted to 1 litre and 100 C.C. of this solution are diluted with an equal volume of water 1 gram of sodium carbonate is added followed by 10 C.C. of the p-phenylenediamine solution (in dilute hydrochloric acid) ; the latter solution should contain from 2 to 6% of the substance and the addi- tion should be made gradually with constant stirring. Benzo- quinonedichloroimide is precipitated as a white substance and with- out filtration the excess of chlorine in the mixture is titrated with N / 10-sodium arsenite solutioa. The difference between this titra- tion and the quantity of arsenite solution required for the titration of the hypochlorite solution itself is equivalent to the amount of chlorine removed from solution as dichloroimide; 1 C.C.of LV/ 10-arsenite solution t.herefore corresponds with 0*0018 gram of p-phenylenediamine. The method may also be used for the estima- tion of p-nitroaniline p-aminodiphenylamine benzidine and naphthyIene-l:4-diamine but with the latter the yield found is ever are optically inactive. w. P. s. and benzoates from an aqueous solution. w. P. s.ii. 134 ABSTRACTS OF CHEMICAL PAPERS. only 98-99% of the quantity of substance present owing to the slight solubility of the dichloroimide formed. The method is not applicable to substances containing a sulphonic group since these give soluble dichloroimides.w. P. s. Estimation of Carbamide in Blood and Urine. H. CITRON (Beut. med. Woch. 1919 45 975; from Chem. Zentr. 1919 iv 719).-A reply to Brahm (this vol. ii 66). H. W. Electrometric Method for the Estimation of Ferrocyanides depending on a Change in Oxidation Potential. G. L. KELLEY and R. T. BOHN (J. Amer. Chem. Soc. 1919 41 1776-1 783).-Solutions of ferrocyanides may be estimated by titraticn with potassium permanganate in the presence of sulphuric acid using the sudden change in E.M.F. observed with a bright platinum electrode to mark the end-point. The method is as follows About 1 gram of potassium ferrocyanide in 250 C.C. of water and 2.5-5-0 C.C. of sulphuric acid (D 1-58> is titrated with 0*@5N-potassium permanganate using an electrometric apparatue which will indicate changes of potential of the order of one millivolt (A.1917 ii 512). A small precipitate may form during the titra- tion but this will redissolve. The titration should be performed slowly with mechanical stirring. As the end-point is approached the permanganate should be added drop by drop and time allowed for the completion of the reaction. The end-point is taken as the point of greatest change in potential for equal additions of permanganate. Should too much permanganate be added the end-point may be approached from the other side by adding a standard solution of ferrocyanide. The presence ot' ferricyanides does not interfere with the titration neither do amounts of chloride up to 1 gram of sodium chloride.Any salts which under the conditions of experiment produce a precipitate with either ferrocyanide or ferricyanide seriously interfere with the method. J. F. S. Use of Silicotungstic Acid in the Estimation of Alkaloids. ERWIN TAIGNER (Zeitsch. anal. Chem. 1919 58 346-352).- Silicot-ungstic acid solution may be used for the quantitative pre- cipitation of atropine strychnine and cocaine from their hydro- chloric acid solutions ; the precipitates formed are collected after the addition of sodium chloride washed with 1% hydrochloric acid dried a t 40° and weighed. The precipitates have the general formula 12W0,,Si0,,2H20,4-a1ka10id. w. P. s. Colour Reactions of Emetine. ABEL LAHILLE (Arch. mkd. exp. 27 296 ; Zerttr. Biochem. Biophys. 1919 20 398) .-Emetine hydrochloride develops a yellow coloration with calcium chloride and with concentrated nitria acid. When a small crystal of ammon- ium molybdate is added to a solution of the hydroohloride in con- centrated sulphuric acid a green zone which subsequentry turns blue is formed round the crystal; the colanr disappear8 on dilutionANALYTICAL CHEMISTRY.ii. 135 with water and reappears on heating. A green coloration is pro- duced when a dichromate is used instead of ammonium molybdate. CHEMICAL ABSTRACTS. The Arsenotungstic Reagent in the Method of Bertrand and Javillier for the Estimation of Nicotine. LUIS GUGLIAL- MELLI and ULAUS HORDH (Anal. SOC Quim. Argentina 1919 7 121-123) .-The preparation of silicotungstic acid for the estima- tion of nicotine by the method of Bertrand and Javellier (A.1909 ii 450) presents difficulties. The authors recommend the use of arsenotungstic acid (Guglialmelli A. 1916 ii 584 587) as a precipitant. The procedure is otherwise unaltered. W. S. M. Ehrlich’s Reaction with p-Dimethylaminobenzaldehyde and Urorosein. E. SALKOWSKI (Biochem. Zeitsch. 1919 97 123-1 29) .-Tb e reaction of p-dimethylaminobenzaldehyde with indole indoleacetic ind olepropionic and indoleaminopropionic acids is described and discussed ~ Herter’s theory concerning the origin of urorosein in urine is also discussed. s. s. z. Estimation of Tyrosine by means of Millon’s Reaction. MORIZ WEISS (Biochem. Zeitsch. 1919 97 170-176).-A 1 /50,000 solution of tyrosine to which Millon’s reagent is added is used as a standard.The solution to be examined is then diluted until it gives with Millon’s reagent a coloration equal to that of the standard. The method can be employed for the estimation of s. s. z. New Method of Estimating Albumin in Urine. DOMENICO GANASSINI and PIETRO FABBRI (Boll. Chim. Farm. 1919 58 313-319).-A method of estimating albumin in urine is based on the fact that the sulphur of the cystinic group in the protein mole- cule is readily detached by the action of hot alkali hydroxide and in presence of lead plumbite yields lead sulphide. On then titrating the liquid with iodine solution the metaproteins are first oxidised and iodised and the lead sulphide is then converted into lead sulphate. I n applying tnhe method from 20 to 100 C.C. of urine (according to the amount of albumin indicated by a pre- liminary test) are mixed with 5% of sodium dihvdrogen phosphate (to prevent precipitation of phosphates of alkaline earth metals) and the liquid heated and stirred for a few seconds until t.he albumin has coagulated.The precipitate is separated washed and dissolved in 10 to 30 C.C. of 10% potassium hydroxide solution from 3.3 to 10 C . C . of 5% normal lead acetate solution added and the beaker immersed for five minutes in boiling water. The liquid is then cooled to 21° and titrated with N/lO-iodine solution which is added a t the rate of two drops per second with continual stirring until the liquid becomes colourless. The number of C.C. of iodine multiplied by 0.0330 gives the quantity of albumin in the amount of urine taken Standard potassium ferricyanide solution may be used instead of iodine solution for the titration but the end-point of the reaction is not so sharp.tyrosine in the products of hydrolysis of proteins. C. A. M.ii. 136 ABSTRACTS OF CHEMICAL PAPERS. Medical Analysis of Urine by the Combined Use of Tungstic Acid and Other Reagents. HUGH CAMPBELL Ross (Brit. Pat. 134710).-When to 2 C.C. of urine 0-2 C.C. of a reagent composed of a 12% aqueous solution of colloidal tungstic acid to which 10% of acetic or tartaric acid to neutralise any possible alkalinity of the urine and 2.5% of sodium potassium tartrate have been added the presence of albumin is indicated by the form- ation of a precipitate which does not dissolve on warming. If the acid is impure an excess of urates also causes a precipitate but it redissolves on boiling the solution.I n the latter case a diabetic condition is indicated and the presence of reducing sugars may be tested for by adding copper sulphate and an alkali hydroxide or preferably for the sake of convenience a tablet containing 0.02 gram of copper sulphate and 0.01 gram each of sodium carbonate and calcium hydroxide. Volumetric Analysis of Ion-protein Compounds. JACQUES LOEB (Proc. SOC. Exp. BioZ. Med. 1918 16 39).-Gelatin a t > 4.7 combines only with cations and at p < 4.7 only with anions whilst a t the isoelectric point (p,=’4.7) it combines with neither anion nor cation. Curves representing the influence of univalent anions or cations on the swelling. osmotic pressure and viscosity of gelatin are always approximately parallel wit.h the curves representing the amount of anion or cation found in chemical combination with the gelatin. Estimation of Pepsin. JOHN H. NORTHROP (J. Gen. Physiol. 1919 2 113-120).-See this vol. i 193. Influence of Acetic Acid on the Benzidine Reaction. EMMO SCHLESINGER and JULIUS GATTNER ( B e d . RZ&. Woch. 1919 56 706-707; from Chem. Zentr. 1919. iv 526).-The discordant views of different authors on the value of the benzidine reaction in the detection of blood are due to the previously unnoticed fact that the sensitiveness of the reaction is a function of the concentration of the benzidine in the acetic acid. The authors find that a blue substance is the actual product of the benzidine reaction; this is precipitated if the proportion of acetic acid to benzidine is low and is thus removed from further action and remains stable for a long period. I n the presence of an excess of acetic acid however it dissolves with the formation of a very unstable. green solution. Diagnostic conclusions cannot therefore be immediately based on the occurrence of one or other coloration since the quantity of acetic acid used is a decisive factor. The blue colour invariably becomes green on addition of acetic acid. Reduced Eosin as a Reagent. LUCIANO P. J. PALET and AMANCIO FERNANDEZ (Anal SOC. Quim. Argentina 1918 5 119-120).-Traces of blood in dilute solution may be detected by means of the fluorescence produced with an alkaline solution of the leu-derivative of essin. The substitution of fluorescein for eosin is recommended. W. S. M ’ G . F. M. CHEMICAL ABSTRACTS. H. W.

ISSN:0368-1769    

DOI:10.1039/CA9201805118

出版商:RSC    

年代:1920

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY. Physiological Chemistry. i. 121 The Absence of the Bromine Reaction for Tryptophan in Tryptically Digested Leucocytes. MORITZ WEISS (Bio- chent. Zeitsch. 191 9 98 116-120).-Tryptically digested leuco cytes do not give the bromine reaction for tryptophan. Putrified pus shows the presence of indole but only traces of indole deriv- atives can be denionstrated in it by the urorosein reaction (hydro- chloric acid and sodium nitrite). The pus cells give a strong Adamkiewicz-Liebermann reaction. M'hilst casein manifests a blue coloration leucocytes give a violet coloration in this reaction. It is concluded that a derivative of tryptophan but not tryptophan Origin of Odour. H. TEUDT (Deutsch. EssiginO. 191 9 23 160-162; from Chem. Zeutr. 1919 iii 239).-The author has beeii able to develop llis t8heory further by a consideration of the atomic models of Rutherford and Bohr and has deduced the causes which are -operative in setting the valency electrons within the molecule into such vibrations as produce odour (compare A.1919 i 607). The original paper must be consulted for details. The Chromium Reaction of Certain Tissues as an Adrenaline Reaction. W. STOELTZNER (Miinch. nted. Woch. 1919 66 584; from (,'hem. Z m t r . 1919 iii 60).-It has. not been observed previously that adrenaline gives the same reaction with chromic acid as certain tissues. A dilute pale yellow solution of potassium dichroniate beconies intensely brown after addition of adrenaline and gradually deposits a brown precipitate. The shade exactly matches the browii coloration assumed by the tissue when treated with dichromate aiid the chroiniuni reaction of the t,issue must therefore be due to adretialine. itself is concerned in the synthesis of leucocytes.s. s. z. H. W. H. W.i. 122 ABSTRACTS OF CHEBECCAL PAPERS. Presence of Haematoporphyrin in the Urine and Faeces of a Case of Acute Haematoporphgrinuria. WILHELM LOFFLER (Biochem. Zeitsch. 1919 98 105-116).-The coloured urine of a patient suffering from Landry’s disease was examined for hmatoporphyrin. The urine was precipitated with glacial acetic acid and the precipitate dissolved in potassium hydroxide. After reprecipitating and redissolving in N / 10-potassium hydroxide the fraction showed the typical spectrum of hmatoporphyrin. A por- tion of the hzmatoporphyrin was methylated by H.Fischer’s method. The compound thus obtained melted a t 262O (not sharp) and gave the same spectrum as Fischer’s preparation. The hydro- lysed methyl ester yielded the original hmatoporphyrin. 0.2 Gram of haematoporphyriii was excreted in twenty-four hours. On extracting the faeces of the same patient by Fischer’s bicarbon- ate method and with methyl alcohol and hydrochloric acid the pres- ence of small quantities of hzmatoporphyrin similar to that extracted by Fischer from a similar source was established. s. s. 2. The Action of Strophanthin on Colloids. GEORG PIETRKOWSKI (Biochem. Zez’tsch. 1919 98 92-104) .-The action of strophan- thin on optically invisible colloidal gold solutions produces an increase in the number of particles visible under the ultra-micro- scope. I n the case of an hydrophile colloid such as gelatin stro- phanthin inhibits imbibition. These facts it is suggested justify the conclusion that the increase in tonus in the cardiac muscles brought about by the action of this drug is due to the shrinking of the surface of the muscle fibres. The above experiments however do not explain the specificity of strophanthin. s. s. 2.

ISSN:0368-1769    

DOI:10.1039/CA9201800121

出版商:RSC    

年代:1920

数据来源: RSC