INORGANIC CHEMISTRY. 21 Inorganic Chemistry. Reduction of Perchlorate by the Wet Method. B. SJOLLEMA (Zeit. anorg. Chern. 1904 42 127-128).-Potassium perchlorate when boiled in aqueous solution with ferrous hydroxide in the absence of free alkali is reduced quantitatively to chloride. A. McK. Rate of Crystallisation o1 Plastic Sulphur. JOSEPH H. KASTLE and WALTER PEARSON KELLEY (Amer. Chem J. 1904 32 483-303).-The rate of change of plastic sulphur into the crystalline variety has been studied by sp. gr. and dilatometric methods. A specimen of sulphur was heated to 200' and poured into cold water ; one portion was left in water a t the ordinary temperature whilst another was kept in water a t 70"; the sp. gr. of each mas determined at intervals of an hour. In another experiment the sulphur was heated to 444" before being poured into water; portions of this specimen were kept at 80° 60° and 40" respectively whilst another portion was left in cold water ; the sp.gr. was determined a t intervals in each case. The results indicate that the rate of change of plaatic into crystalline sulphur varies according to the temperature to which the sulphur is heated before being poured into water and also with22 ABSTRACTS OF CHEMICAL PAPERS. the temperature a t which the product is preserved. The higher the initial temperature to which the sulphur is heated the slower is the crystallisation ; and the higher the temperature at which the sulphur is kept the more rapid is the change. I n another series of experiments a specimen of plastic sulphur was divided into five portions which were kept under water dilute ammonia 95 per cent.alcohol dilute bromine water and N/10 iodine solution respectively the sp. gr. being determined at intervals in each case. It was found that ammonia alcohol and bromine accelerate whilst iodine retards the crystallisation. A study of the effect of heat has shown that plastic sulphur has no definite melting point the effect of any increase of temperature being merely to diminish its viscosity and to increase its tendency t o pass into the crystalline form. The stability of any particular specimen of plastic sulphur can be judged from its colour ; light amber-coloured specimens crystallise easily whilst reddish-brown varieties remain plastic for longer periods. Experiments have shown that when the plastic and orthorhombic forms of sulphur are heated a t 120-125' for a sufficient length of time they become alike in colour a state of chemical equilibrium being ultimately reached in each case.Experiments made with the object of determining the effect of tension on the crystallisation showed that specimens of sulphur under tension crystallise more rapidly than those not under tension. Determinations of the rate of change by the dilatometric method showed that plastic sulphur prepared by pouring into water sulphur that has been heated only to a moderately high temperature crystallises rapidly whereas that which has been heated to near the boiling point before being poured into water crystallises very slowly. The velocity of the change of plastic into crystalline sulphur begins comparatively rapidly about 10 per cent.of the total change taking place in the first 30 minutes and then gradually diminishes. This gradual decrease in the rate of crystallisation indicates that several molecular forms are present in the supercooled liquid some of which change to the crystalline variety of the element more rapidly than others. E. G. The Chlorides of Sulphur. Sulphur Tetrachloride and its Compounds. OTTO RUFF (Ber. 1904 37 4513-4521. Compare Ruff and Fischer Abstr. 1903 ii 204).-The author has re-examined the double compounds of sulphur tetrachloride described in the literature and has corrected some erroneous analyses. The so-called sulphur dichloride was employed in the preparations and the author's view is confirmed that this substance is a solution of largely dissociated sulphur tetrachloride in sulphur chloride.Sulphur tetrachloride prepared by the slow combination of sulphur chloride with liquid chlorine in a sealed tube is st yellowish-white substance melting a t - 30.5'to - 31' t o a red liquid. Its dissociation pressure reaches 1 atmosphere a t a few degrees above its melting point. Water decomposes it in a sealed tube almost quantitatively forming sulphurous acid.INORGANIC CHEMISTRY. 23 The double compounds of sulphur tetrachloride are designated by their forruulze. [With GEORG FL~CIIE~L ]-The coinpound SCl,,SbCI prepared by adding sulphur chloride to .a cold solution of aritiinouy peritachloride in sulphuryl chloride and draining by means of the apparatus described by Ruff and Plato (Be?- 1901 34 1749) forms slender white needles melting a t 125-126" in an atmosphere of chlorine in a sealed tube to a yellow liquid and subliming a t 150'.Water decomposes it vigorously. No solid compound could bt. obtained from sulphur tetra- chloride and phosphorus pentachloride. The salt SC14,TiC14 crystallises in slender yellow needles of ten radially grouped melts at 62-64" in an atmosphere of chlorine sublimes at about 1 00" and dissolves in sulphuryl chloride chloroform carbon disulphide or light petroleum. 2SC1,,SnC14 forms large yellow crystals melts a t 37" and de- coiriposes at about 40". It fumes in air but is more stable than the titanium compound and dissolves readily in chloroform light petroleum sulphuryl chloride carbon disulphide phosphorus oxy- chloride ether or benzene.The corresponding compound with zirconium tetrachloride is very unstable and could not be isolated in a pure form. A silicon compound could not be obtained. [With ETNBECK.]-~C~,,F~C~ prepared in phosphorus oxychloride solution forms a yellow crystalline precipitate decomposing rapidly on warming. The compound 2FeCl3,POC1 was obtained on warming the constituents together on the water-bath in the form of a bright yellow crystalline mass. [With GEORG FISCHER.] -SCl4,2IC1 forms yellow crystals de- composing without fusion on even slight warming. No compounds could be obtained from arsenic trichloride antimony trichloride or chromic chloride. [With KURT TRIEL.]-SC~,,~ASF~ forms yellow crystals and only attacks glass slowly but decomposes or chars thionyl chloride carbon tetrachloride carbon disulphide alcohol ether benzene or light petroleum.No compounds were obtained from antimony tin or titanium fluorides or from the chlorides of uni- or bi-valent metals. G'. H. D. Theory of the Lead Chamber Process. 11. FRITZ RASCITICI A reply to (Zeit. angew. Chern. 1904 17 1777-1785).-Polemical. Lunge (ibid. 1659). A. McK. Catalytic Phenomena in the Preparation of Persulphuric Acid. G. I. PETRENKO (J. Buss. Phys. Chena Xoc. 1904 36 1081-1OSS).-The yield of persulphuric acid obtained by the electro- lysis of sulpliuric acid is dependent on the use of a platinum anode which apparently oxidises and then exerts a catalytic action diminish- ing the yield of the peracid.The yield of the latter is almost doubled by the addition of hydrochloric acid. With an iridium anode the yield is considerably less than with platinum and the iridium goes into solution more readily than platinurn. T. 13. P.24 ABSTRACTS OF CHEM1CA4L PAPERS. Ultramicroscopical Observations. I. Separation of Sulphur from Thiosulphuric Acid and of Selenium from Selenious Acid. WILHELM BILTZ and WILLY GAHL (Chem. Centr. 1904 ii 1367 ; from Ncichr. K. Ges. JViss. Gottingen 1904 300-310).-By means of Raehlmann’s ultr.imicroscope homogeneous or ‘‘ optically empty ” solutions may be more readily distinguished from turbid solutions and the phenomena of precipitation more closely followed. By means of the arrangement used a field of 0*00004 cm. was illumin- ated.Filtration or contact with cover glasses or india-rubber destroys the optical homogeneity of solutions. Distilled water must be rendered clear before distilling and must be protected from access of air during distillation and afterwards. A Pukall cell may be used for filtration the air which enters the filter being made to pass through cott on-wool. Thiosulphuric acid decomposes as soon as it is formed the non-dis- sociated acid being the less stable. By means of the ultramicroscope it has been shown that the process of decomposition is not ‘‘ continu- ous,” the discontinuity becoming apparent a t about the same time as the opalescence is visible to the naked eye. Colourless supersaturated solutions of the acid in water can therefore exist. Colloidal aqueous solutions of the acid appear to be blue and are extremely unstable.The action of sulphurous acid on selenious acid has also been found to be optically discontinuous. E. w. w. Colloidal Tellurium. IV. ALEXANDER GUTBIER (Zeit. anorg. Compare Abstr. 1902 ii 653; 1904 Chenz. 1904 42 177-183. ii 61 3).-A detailed account of results already published. A. McK. Action of Hydrogen Peroxide on Tellurium. ALEXANDER GUTBIER and F. RESENSCHECIC (Zeit. ccnorg. Chefiz. 1904 42 174-176. Compare Gutbier and Wagenknecht Abstr. 1904 ii 613).-When hydrogen peroxide is added to a solution of tellurium in concentrated aqueous potassium hydroxide telluric acid is produced in small yield. A. McK. Apparatus for Separating Nitrogen Quickly and Com- pletely from a Mixture of Gases containing it.FERDINAND HENRICH (Zeit. angew. Chern. 1904 17 1755-1757).-An apparatus is described by means of which nitrogen is separated automatically from a mixture of gases containing it the mixed gases being repeatedly passed over heated copper and copper oxide soda lime phosphoric oxide and a heated mixture of magnesium and quicklime. A full descrip- tion is appended to the sketch of the apparatus in question. A. McK. Formation of Nitric Oxide at High Temperatures. WALTHER NERNST (Chem. Centr. 1904 ii 1368 ; from Nachr. k. Ges. Vhs. Gottinyen 1904 261-276. Compare Muthmann and Hofer Abstr. 1903 ii 206).-If a system which is in equilibrium at a high tempera- ture is rapidly cooled the composition of the mixture at the lowerINORGANIC CHEMISTRY. 25 temperature will not accurately represedt the condition a t the higher since the cooling cannot be effected instantaneously.I n all cases no matter in which direction the composition of the gaseous mixture deviates from thatl of the equilibrium state the proportion of the product formed at the higher temperature will be too small except for a small temperature interval in which the curve calculated from thermodynamical data touches that obtained from observed values. I n cases in which it is impossible t o allow sufficient time for the state of equilibrium to be attained because the temperature is too low and the velocity of the action too small the velocities of the opposing reactions may be measured by experiments on streams of gas at different velocities. The concentration at which both reactions have the same velocity and hence the equilibrium constant may be calcu- lated.When gases are brought to very high temperatures for a very short time as for instance when a mixture of hydrogen and oxygen in the proportions contained in water is exploded with air and the mixturd rapidly cooled an examination of the products of the explosion may serve under certain conditions to ascertain the conditions of equilibrium at such temperatures. A litre of air was passed through platinum or iridium tubes and the nitric oxide absorbed in sulphuric acid. The temperature was estimated by means of a thermo-element or a photometer. At temperatures above I 700° equilibrium was attained when one litre passed through the tube in 20 minutes. At 1760° the equilibrium concentration of the nitric oxide was found to be 0.64 per cent,.by volume and at 1922' 0.97 per cent. The "heat-toning" of the reaction calculated from these data is 45,600 cals. whilst the value found by experiment was 43,200. A state of equilibrium could not be obtained in the platinum furnaces a t 153s'. The velocities of the opposing reactions show that the reaction is bimolecular and that the equilibrium concentration of the nitric oxide is 0.37 per cent. by volume. From Bunsen's deter- minations of the decrease of volume caused by exploding mixtures of hydrogen and oxygen with air i t has been calculated that at 3500' the mixture contains about 5 per cent. by volume of nitric oxide when equilibrium is established. Under the ordinary atmospheric pressure t,he time required to convert half the nitrogen of air into nitric oxide is about 100 seconds a t 1540O and 3.5 a t 1737'.The following table shows the observed and calculated equilibrium constants x a t tempera- tures from 1500-3200° Temp. (abs.). x observed. x calculated. 181 1" 0.37 0.35 2033O 0.64 0.67 2 195O 0.97 0.98 3200' about 5 4.4 E. W. W. Preparation of Yellow Arsenic. ALFRED STOCK and WERNER SIEBERT (Ber. 1904 37 4572-4575).-A special form of apparatus is described and figured by means of which arsenic is sublimed in a vacuum and the vapour immediately cooled by liquid air. Under26 ABSTRACTS OF CHEMICAL PAPERS. these conditions a yellow modification of arsenic is deposited which when exposed to light is instantly converted into the black modifica- tion.A similar change takes place in the dark when the yellow form is allowed to assume the ordinary temperature but the change is not accompanied by any luminescence phenomena. E. F. A. The Preparation of Pure Boron Trifluoride and Silicon Tetra- fluoride and some Physical Constants of these Compounds. HENRI MOISSAN (Conzpt. rend. 1904 139 71 1-714).-Boron tri- fluoride prepared by heating a mixture of boron trioxide calcium fluoride and sulphuric acid and purified by passing through cylinders containing sodium fluoride and finally by solidifying in a vacuum (compare Abstr. 1903 ii 642) melts a t - 127" and boils a t -101' (compare Abstr. 1904 ii 331); the corresponding constants of the synthetical compound are - 126' and - 99' respectively. Silicon tetrafluoride similarly prepared and purified and also the synthetic compouT\-d solidifies at - 9 7" under atmospheric pressure and volatilises without passing through the liquid stage (compare Olszewski Abstr.1884 816) under tt pressure of 2 atmospheres. Silicon tetrafluoride melts a t - 77' t o a transparent mobile liquid which boils a t - 65' under 181 cm. pressure ; the critical temperature is - 1.5" and the critical pressure 50 atmospheres. M. A. W. Action of Boric Acid on the Alkali Peroxides. Formation of Perborates. GEORGE F. JAUBERT (Compt. rend. 1904 139 796-798).-When an intimate mixture of 248 grams of boric acid and 78 grams of sodium peroxide is gradually added to 2 lltres of cold water .a clear solution is first obtained from which the perborate Na2B,08,10H20 crystallises after a time in 90 per cent.yield. The aqueous solution of the perborate contains free hydrogen peroxide. Its solubility at ll' 22") and 32" was found to be 42 71 and 138 grams per litre. The perborate cannot be recrystallised from its aqueous solution When a quantity of hydrochloric acid equivalent to half the sodium in the perborate is added to this solution a perborate NaB03,4H20 separates in the form of white crystals which are very stable a t the ordinary temperature and are not affected by atmospheric carbon dioxide. This salt is less soluble than the first perborate ; its aqueous solution slowly decomposes at 50-60" and evolves oxygen rapidly a t 100". The solution has all the properties of hydrogen peroxide and on account of its stability in the air the crystalline salt may con- veniently be used as a means of obtaining an aqueous solution of hydrogen peroxide. H.M. D. Tension of Carbon Dioxide in Sea Water and the Reciprocal Influence of the Carbon Dioxide of the Sea and of the Atmos- phere. AUGUST KROGH (Conapt. rend. 1904 139 896-898).-The ocean contains about 6-55 x 10IG kilograms of carbon dioxide in the form of readily dissociated salts or twenty-seven times the quantity containedINORGANIC CHEMISTET. 27 in the atmosphere and the variation of this quantity with the pressure is expressed in the following table Pressure per cent. Quantity in kilos. 0.01 4.57 x 1016 0.02 5.89 x 1016 0.03 6.55 x 1016 0.04 7.04 x 10'6 0.05 7.36 x 1016 A series of determinations of the tension of carbon dioxide in the sea and in the atmosphere has given the following results (1) in the north af the Atlantic Ocean the tension of carbon dioxide is much lower in the water than in the atmosphere; (2) the atmosphere over the Atlantic Ocean and its shores contains less carbon dioxide (0.029 per cent,) than in Central Europe (0.033 per cent.) ; (3) in the south- ern hemisphere where the ocean covers the major part the atmosphere contains less carbon dioxide than in the northern hemisphere (0.026 per cent,).It follows therefore that the percentage of carbon dioxide in the atmosphere is increasing and that the sea compensates for the increase by absorbing the gas. M. A. W. Action of Potassium Cyanide Solution on Various Metals. ANDRI$ BROCHET and JOSEPH PETIT (Bull.Xoc. chim. 1904 [iii] 31 1255-1257. Compare Abstr. 1904 ii 229 230 and 414).-Alumin- ium and magnesium are readily attacked in the cold by potassium cyanide solution copper and zinc less readily yielding respectively the salts Cu2(CN),,6KCN and Zn(CN),,2KCN and other metals very slowly except on heating. Cadmium and silver are attacked by potassium cyanide solution in presence of oxygen but mercury is unaffected and the amalgamation of a metal retards the action of the salt on it. Deville and Debray (Compt. rend. 1876 82 241) and Glaser (Abstr. 1903 ii 242) have shown that platinum dissolves in solutions of potassium cyanide. The author finds that this does not occur unless the solution of the cyanide is heated and that the effect is diminished by polishing the platinum.T. A. H. Action of Potassium Cyanide on Metallic Electrodes ANDRB BROCHET and JOSEPH PETIT (BUZZ. Xoc. chim 1904 [iii] 31 1257-1261. Compare Abstr. 1904 ii 229 230 and 414).-Most metals behave as soluble anodes when placed in potassium cyanide solution under the influence of an alternating current. A number Q€ metals including copper zinc silver and cadmium dissolve quantita- tively when the current is weak. Nickel dissolves quantitatively so long as the current does not exceed 2 amperes per sq. decimetre; beyond this the dissolution diminishes reaching a minimum of 80 per cent of the theoretical when the current density is 8 amperes per sq decimetre (compare Le Blanc and Schick Abstr. 1904 ii 230). Cobalt dissolves irregularly and the anode becomes pitted.Mercury is almost immediately covered by a black precipitate which preventa28 ABSTRACTS OF CHEMICAL PAPERS. further action but amalgamation has no effect on the dissolution of copper and zinc. Silver begins to deposit on the cathode almost as soon as it appears in the electrolyte and cadmium behaves similarly but copper zinc and nickel deposit only with difficulty whilst with cobalt and iron no deposition occurs. The observation of Glaser (Abstr. 1903 ii 242) that platinum is dissolved when employed as a cathode in potassium cyanide solution is confirmed and it is shown that the action is much more marked when barium cyanide is employed as the electrolyte. This dissolution of platinum under these conditions is due to the disintegration of the cathode probably with the transitory formation of an alloy with the alkali metal and the dissolution in the electrolyte of the finely-divided platinum particles so liberated (compare Bredig and Haber Abstr.1899 ii 78; Hnber and Sack Abstr. 1902 ii 441 ; Bran ibid. ii 442). I n favour of this view is the slow evolution of hydrogen which takes place from the cathode immediately after the current has been stopped. Lead is almost without action. T. A. H. Theory of the Dissolution of Metals in Potassium Cyanide Solution u n d e r t h e Influence of an Alternating Current. ANDRE BROCHET and JOSEPH PEwi7 (&d$. 8oc. dim. 19(:4 31 126 1- 1265. Compare preceding abstracts).-Such metals as silver which are quantitatively dissolved from the anode and deposited on the cathode are insoluble in potassium cyanide solution under the action of an alternating current.On the contrary copper zinc nickel and cobalt which are either not deposited or deposited only with difficulty are soluble in potassium cyanide solution. The cases of iron and platinum which behave as insoluble anodes and slightly soluble cathodes and yet are readily dissolved by potassium cyanide solution under the action of an alternating current are not so easily explicable. Platinum also dissolves in the cyanide solution under the action of a continuous current frequently interrupted and it is probable that its dissolution is due to disintegration while it momentarily acts as a cathode the dissolution of the detached particles being facilitated by the oxidising action of the platinum electrode immediately afterwards functioning as an anode.The original paper contains a series of curves showing (a) the influ- ence of current frequency (from 5 to 100 per second) on the rate of dissolution of various metals and (6) the simultaneous influ- ence of current density and frequency on the rate of dissolution of nickel. The first set of curves shows that as the frequency is increased copper dissolves less quickly whilst iron nickel and cobalt exhibit a maximum and then diminish; with platinum the maximum is unattainable under these conditions. The second series of curves appears to shorn that nickel behaves like copper when the current density is less than 7 amperes per sq. decimetre but above this behaves like iron and that when frequency and density are simultaneously and sufficiently increased no solution should occur.The latter deduc- tion is not in harmony with the experimental observation recorded in the preceding abstract. T. A. H,INORGANIC CHEMISTRY. 29 Reactions between Salts in Non-aqueous Solutions. 11. In Acetone. ALEXANDER NAUMANN [and in part with WILHELM EIDMANN MAX M~LLER PAUL SC'HULZ and ERNST VOIC-T] (Bey. 1904 37 4328-4341. Compare Abstr. 1904 ii 819).-Pure anhydr- ous acetone of sp. gr. 0.795 a t 1 8 O f 4 O was used. The following salts are readily soluble aluminium bromide nminonium bromide tri- chromate iodide nitrate perchlorate and thiocyanate ; antimony tri- bromide chloride (0*186) and iodide ; barium bromide and iodide ; bromine ; cadmium bromide (64.5) chlorate iodide (4) and nitrate ; cmiuru nitrate ; calcium bromide chlorate dichromate iodide and nitrate ; cerium bromide chloride iodide and nitrate ; chromic nitrate ; chromic anhydride ; ferric chloride (1.59) and nitrate ; ferrous chloride ; erbium nitrate ; iodine ; potassium bromide chloro- chromate ferricyanide ferrocyanide iodide permanganate mercuri- iodide and thiocyanate ; cobalt chloride (36*4) bromide iodide and nitrate ; cupric bromide chloride (34*7) and chlorate ; lanthanum nitrate ; lithium bromide chloride iodide and nitrate ; magnesium bromide chlorate chloride and iodide ; palladous chloride ; platinic chloride ; mercuric chloride ( O T ) bromide and nitrate ; rubidium nitrate ; sulphur ; silver nitrate (22'7) and nitrite ; thallous nitrate ; uranium bromide ; uranyl chloride iodide and nitrate ; bismuth tri- chloride (5.59) and tri-iodide ; zinc chloride (2.3) and iodide ; stannous chloride (1 ' 8 ) ; stannic chloride bromide and iodide.The numbers in brackets indicate the number of grams of acetone required to form a saturated solution with 1 gram of the salt a t 18". The following salts are very sparingly soluble aluminium chloride and nitrate ; ammonium chromate diborate and thiosulphate ; barium chlorate and nitrate ; lead bromide and nitrate ; cadmium chloride ; calcium chloride ; potassium nitrate ; lithium diborate ; sodium di- chromate ; mercuric iodide ; rubidium bromide ; strontium chloride and nitrate ; thallic chloride ; thorium nitrate. A list of some 197 insoluble compounds is given. Ammonia yields precipitates with acetone solutions of the following salts cupric bismuth antimony cobaltous mercuric stannous and ziuc chlorides silver nitrate cadmium bromide and cadmium iodide.The pre- cipitates in all cases are additive compounds of the salt and ammonia. The following yield precipitates of silver haloids with silver nitrate in acetone solution bismuth antimony ferric cobaltous mercuric strontium and zinc chlorides cadmium bromide arid iodide. Hydrogen sulphide precipitates the metals of stannous chloride bismuth chloride silver nitrate and cadmium bromide as sulphides. It precipitates mercuric chloride as HgC1,,2HgS and cadmium iodide as CdI,,BCdS. Double decomposition has been observed between cadmium bromide and mercuric chloride cupric chloride and calcium bromide bismuth chloride and potassium iodide mercuric chloride and cadmium iodide mercuric chloride and bismuth iodide and also between potassium thiocyanate and solutions of the following salts zinc chloride silver nitrate and cobalt chloride.Cupric ferric and mercuric chlorides are reduced by stannous chlor- ide. Ferric and cupric chlorides are reduced by potassium iodide and ferric chloride partially by hydrogen sulphide.30 ABSTRACTS OF CHEMICAL PAPERS. Acetone solutions of silver nitrate yield precipitates with hydrogen qhloride bromide or iodide and in the case of the bromide and iodide the precipitate dissolves in an excess of the acid. Silver nitrate and sulphur yield Ag,S,. Mercuric chloride and cuprous bromide yield mercurous bromide cuprous chloride and chlorine ; cadmium bromide is decomposed by an acetone solution of chlorine and cuprous chloride which is insoluble in acetone yields with an acetone solution of chlorine cnprbc chloride with bromine a mixture of cupric chloride and bromide and with an iodine solution cuprous iodide and capric chloride.Mercurous chloride suspended in acetone is only slightly affected by chlorine but with bromine and iodine yields mixtures of mercuric chloride with the bromide and iodide. J. J. S. Reactions between Salts in Non-aqueous Solutions. 111. 4609-4614. Compare Abstr. 1904 ii 819).-The solubility of a large number of inorganic salts in pyridine was determined qualitatively. The compound HgC12,C5H,N prepared by the addition of mercuric chloride to pyridine crystrtllises in needles.I t s behaviour when dissolved i n pyridine towards ammonia hydrogen sulphide and stan- nous chloride is similar to that of mercuric chloride. With ammon- ium thiocyanate and silver sulphate it gives precipitates of ammonium chloride and mercuric sulphate respectively. The compound CuC1,,2C5H,N prepared by the addition of cupric chloride to pyridine separates from alcohol in needles. I t s behaviour and that of the compound AgN0,,2C5H,N (in pyridine solution) and of a solution of silver sulphate in pyridine towards various reagents is described in considerable detail. ALEXANDER NAUMANN [and JOHANNES SCHROEDER] (Bey. 1904 37 A. McK. Sodamide and certain of its Reaction Products. W. PHILLIPS WINTER (S. Amer. Chem. SOC. 1904 26 l.484-1512).- A convenient method is described for the preparation of sodamide. When sodamide is exposed to dry air it slowly assumes a yellowish- brown colour and is found to contain nitrous and hyponitrous acids.When sodamide is decomposed by water hydrogen and nitrogen are produced. The relative proportions of these gases vary with the con- dition of the sodamide. It has been found that the proportiou of hydrogen is high in the case of sodamide which has been insufficiently heated owing to the presence of unchanged sodium but is low when the sodamide has been properly prepared. Nitrogen is always evolved to a small extent and is formed in larger proportion from sodamide which has been kept for some time than from freshly prepared speci- mens. The production of the nitrogen is probably due to the presence in the sodamide of sodium azoimide or some analogous compound formed by oxidation of ammonia either in the process of manufacture of the sodnmitle or during its exposure to dry air.If finely powdered sodamide is sprinkled into a vessel containing water heated ncarly to boiling through which a current of carbonINORGANIC CHEMISTRY. 31 dioxide is being passed a shower of brilliant sparks is piocluced and a solution of disodium cyanamide is formed. When sodamide is treated with phosphorus pentachloride a violent reaction takes place and a white sitblirnnte is produced which consists of ammonium chloride sodium chloride traces of phosphorus com- pounds a i d a small quantity of a substance iiisoluble in water. This insoluble compound cannot be isolated but when the soluble substances are removed from the sublimate by means of nitric or acetic acid a white nearly tasteless odourless con~poz~nd PO,N or PH,O,N is obtained which is not affected by hot strong mineral acids.When sodamide is warmed with yellow phosphorus an energetic reaction occurs and the product consists of sodium phosphide and other substances including oxy-acids of phosphorus and probably a n amide of phosphorus. E. G. Supercooled Fusions and Solutions of Sodium Thiosulphate. STEWART W. YOUNG and J. P. MITCHELL (J. Amer. Chenz. Soc. 1904 26 1389-1 413).-Sodium thiosulphate pentahydrate exists in three forms the ordinary commercial or a-form the @form described by Parmentier and Amat (Abstr. 1884 S19) and the y-form discovered in the course of the present investigation The p-form is obtained most readily by heating the a-form at 80-100" for a few minutes in a sealed glass tube and cooling to - 10" or - 20° when the product solidifies in long needles.The y-form is produced occasionally instead of the p-form; the conditions necessary for its formation have not been fully investigated but it appears tbat the presence of a small excess of water in the tube favours its production. This y-modification is obtained as a compact opaque mass which melts a t a little above Oo whilst the p ar,d a-forms melt a t about 32' and 49" respectively. Each ol these forms on melting is converted into a saturated solution and a lower hydrate. The a-form is obtained when the a-pentahydrate is melted and left a t the ordinary tempera- ture for a day or two.The 6-form is produced by the partial fusion of the a-form the d-form by the partial fusion of the P-pentahydrate and the c-form by the partial fusion of the y-pentahydrate. A large number of experiments have been made with the object of ascertaining the conditions under which these various forms are produced from supercooled solutions and fusions attention being paid particularly to the form of the thiosulphate from which the solution or fusion was prepared the rate a t which the tubes were cooled the temperature to which they were heated and the length of time for which the heating was continued For the details of these experiments and the results obtained the original must be consdted. I n order to afford an explanation of the results of this investigation a hypothesis is put forwnrd based on that proposed by Jaff6 (Abstr.1903 ii 469) which ascribes the initiation of the crystallisation to the preseiico of nuclci. It is suggested that these nuclei consist of frag- ment s of crystalliiic aggregates left in the licliiid after the breaking down of the crystnlliiie structure and that under certain conditions. Four different lower hydrates are described.3 2 ABSTltACTS OF CHEMICAL PAPERS they unite to form crystalline aggregates which are capable of starting the crystallisation. E. G. Composition and Solubility of the Hydrates of Sodium Thiosulphate. STEWART W. YOUNG and W. E. BURKE (J. Amer. Chern. Soc. 1904 26 1413-1422. Compare preceding abstract).- Considerable clifficul ty was experienced in determining the composition of the various hydrates of sodium thiosulphate owing to the fact that all the other forms are metastable with respect to the a-form and are rapidly converted into this form if a trace of it is present. Parnientier and Amat (Abstr.1884 819) have shown that the p-form consists of a pentahydrate. There is little doubt that the y-form is also a penta- hydrate although hitherto it has not been analysed. Analyses have been made of the a- 6- and d-forms which show that the first two consist respectively of a monohydrate and a dihydrate and that the d-form is probably a tetrahydrate. The composition of the c-variety has not been ascertained Determinations of the solubility of these different hydrates have given the following results which are expressed as the number of parts of the anhydrous salt Na,S,O in 100 parts of water.The solubility of the a-form of sodium thiosulphate is 59.69 at lo' 70.07 a t 20' 75.90 a t 25' 82.45 at 30° 91.24 at 35O 103.37 at 40' and 123.87 a t 45'. I n the case of the p-form the values obtained were 97.55 a t ZOO 108.98 a t 25O 119.69 at 2S0 12650 a t 29*5O and 130.26 at 30'. The solubility of the a-form is 163.92 at 20° 168.32 a t 25' and 174.20 a t 30'. For the b-form the values found were 122.68 at ZOO 127.43 a t 25' 13397 at 30° 138.84 at 35O 144.92 a t 40° and 165.11 at 50'. In the case of the d-form the solubility was found to be 141.45 at 33.5' 153.23 a t 36.2' and 168.82 a t 38.6O. The solubilities of the y- and e-forms have not been determined.These solubility data have been plotted as curves which are of particular value as defining exactly the ranges of supercooling and supersaturation of the forms studied. E. G. Formation and Constitution of Bleaching Powder. NAZARENO TARUGI (Gaxxetta 1904 34 ii 254-260).-The author finds that the formation of bleaching powder containing a maximum amount of active chlorine is influenced by the presence of oxygen. When lime is completely hydrated and left in contact with air after some time it exhibits the reactions of peroxides-blue coloration with guaiacum resin red coloration with ferrous sulphate and potassium thiocyanate and blue coloration with chromic acid and ether. I n the formation of bleaching powder the chlorine acts on the water yielding hydrogen chloride and oxygen the latter then converting a part of the lime into calcium peroxide 4C1+ 2H,O = 4HCl+ 0 ; CaO,H,O + 0 = CaO,,H,O ; CaO,,H,O + 2HC1= Ca02C1 + 2H,O.The author's experiments indicate that hypochlorites must in general be regarded as chlorides of peroxides and that bleaching powder containing 44.09 per cent. of chlorine (which is the maximum proportion obtainable in the commercial product) is the chloride ofINORGANIC CHEMISTRY. 33 calcium peroxide plus 1 mol. of water Ca(OC1)2,H,0. This constitu- tion for bleaching powder is in accord with its action on mercury which is converted quantitatively into mercuric chloride Ca0,C12 + Hg = CaO + HgC1,. This method is the subject of a patent for the manufacture of corrosive sublimate.T. H. P. Action of Water on the Phosphates of Calcium. FRANK K. CAMERON and ATHERTON SEIDELL (J. Amer. Chem. Soc. lY04 26 1454-1463. Compare Rindell Abstr. 1902 ii 208).-A study has been made of the extent to which the three calcium phosphates are decomposed by water and experiments have been made to ascertain the effect of calcium sulphate calcium carbonate and carbon dioxide on the hydrolysis. Since tricalcinm phosphate and monocalcium phosphate always contain an excess of either base or acid the results of the solubility determinations cannot be regarded as of absolute value but are useful as indicating the nature of the reaction between the phosphates and water. I n each experiment a weighed quantity of the phosphate was placed in x bottle with distilled water and maintained for several weeks at 25".with occasional shaking. Portions of the clear solutions were withdrawn and the amounts of calcium and phosphoric acid in them were estimated. The results shorn that tricalcium and monocalcium phosphates both undergo considerable decomposition but that di- calcium phosphate is more stable and only slightly decomposed by water. I n the case of the mono- and tri-calcium phosphates the amouiit of decomposition and the concentration of the resulting solu- tion are found to depend on the relative proportions of phosphate and water employed. I n presence of calcium sulphate the amount of phosphoric acid dissolved from tricalcium phosphate is increased. A slight increase also takes place with monocalcium phosphate but a considerable decrease occurs in the amount of phosphoric acid dissolved from the dicalcium salt.I n presence of calcium carbonate the amount of phosphoric acid dissolved is decreased in all three cases. Carbon dioxide causes an increased quantity of phosphoric acid t o be dissolved from tri- or di-calcium phosphate but is without effect on the action of water on the monocalcium salt. E. G. Action of Amalgams on Solutions. GUSTAVE FERNEKES (J. Physical Chem. 1904 8 566-570).-A reply to some criticisms by G. McP. Smith (Abstr. 1904 ii 400) of the author's explanation of the action of amalgams on water (Abstr. 1904 ii 263). The author adds the results of some further experiments. It was first shown that barium is not replaced in its rmalgam by either sodium or potassium when acted on by n concentrated solution of a salt.It was found however that barium amalgam reacts with water about three times as quickly as with a solution of potassium chloride. This is readily explic- able on Kahlenherg's theory as each molecule of the salt would influence the surrounding water molecules. Molecular quantitios uf VOL. LXXXVIII. ii. 3ABSTRACTS OF CHEMICAL PAPERS. 34 sodium and potassium chlorides were also allowed to act on sodium amalgam for 15 minutes a t the end of which time the amalgam was found to contain only potassium; this fact and also the anomalous behaviour of sodium hydroxide solutions are not explicable by the ionic theory. L. M. J. Equilibrium in the System G10 SO H20. CHARLES L. PARSONS (J. Amer. Chem. Soc. l904,26,1433-1446).-It is found that the only definite hydrated sulphat es of glucinum are GlS0,,4H20 and GlS04 2H20 no evidence being obtainable of the existence of the heptahydrate de- scribed by Klatzo (Zeit.Chem. 1869 12 129). The tetrahydrate has an aqueous vapour pressure equal to or greater than the pressure of its own water of crystallisation; it has been found by tensimeter experi- ments that this pressure over phosphoric oxide at 20" is equivalent to 20 mm. of olive oil and increases rapidly with the temperature The dihydrate is stable in the air a t the ordinary temperature but loses water slowly at 100-110". The anhydrous sulphate cannot be ob- tained quite pure on account of the difficulty of removing the last traces of water without incurring the loss of sulphur trioxide.An examination of the various so-called basic sulphates of glucinum has shown that these substances are not definite compounds but consist of solid solutions of the sulphate in the hydroxide. E. G. Zincum Boricum or Oxyboricum. E. HOLDERMANN (Arch. P&arm. 1904 242 567-56S).-When a solution of zinc sulphate and another of borax are mixed in varying proportions the second solution containing also just enough sodium hydroxide to complete the conver- sion of the sulphate into sodium sulphate the filtrate gives no further precipitate with either solution when the zinc sulphate and borax have been mixed in the proportion of 3 2 mols. The composition of the precipitate therefore is Zn,(B,O,),(OH),. The Complexity of Dissolved Sulphates. ALBERT COLSON (Cornpt.rend. 1904 139 857-859. Compare Abstr. 1904 ii 377 532).-A solution of copper sulphate containing 0.75 gram-moi. in 2 litres gave a depression of the freezing point of 0.70° whilst the sulphuric acid solution obtained by exactly precipitating the copper in khe same solution by hydrogen sulphide gave a depression of 1-51" at least twice 0*70°; it follows therefore that the second solution contains twice as many molecules as the first and the molecular com- plexity of copper sulphate in solution is represented by the formula (CUSO,)~ and similar results were obtained in the case of magnesium sulphate. The author suggests that the sulphates of the bivalent metals in aqueous solution have the formula (HSO,M),O and may be regarded as being formed by the condensation of 2 mols.of sulphuric acid with the hydroxide (OH*M),O ; this explains the acidic nature of the metallic sulphates. On the other hand the metallic hydroxides are sufficiently strong bases to displace sodium or ammonium hydr- oxide from solutions of their sulphates for when a solution of sodium sulphate is added to zinc oxide neutral to phenolphthalein suspended in water the mixture becomes increasingly alkaline towards the indi- C E. B.INORGANIC CHEMISTRY. 35 cator owing to the liberation of sodium hydroxide and the formation of the basic salt SO,(ZnaO*ZnOH),; similarly a blue coloration is developed when copper oxide is added to a solution of ammonium sulphate. M. A. W. A New Cause of Dissociation of Mercuric Chloride and its Influence on the Antiseptic Properties of Solutions of Corro- sive Sublimate.HENRI VITTENET (Bull. SOC. chin$. 1904 [iii] 31 1133-1138).-When equal parts of ammonium and mercuric chlorides are dissolved in tap-water there slowly forms a precipitate which is a t first white and has the composition N(HgCl) but on further standing gradually becomes yellow. The production of this substance was traced to the presence of acid carbonates in the water and its forma- tion was found to be inhibited by previous ebullition of this. When the two salts are dissolved in distilled water to which sodium hydrogen carbonate or carbonate has been added the precipitate formed is white and has the composition N(HgC1),,3NH4C1 but gradually becomes yellow when washed with water and the final product is bright yellow and has approximately the composition required by the formula N(Hg*OH),*Hg*OCl.The formation of these precipitates in such solu- tions used as antiseptic baths leads t o a diminution of efficiency and it is suggested that in preparing these the water should first be boiled or t'he ammonium chloride should be replaced by sodium chloride; with either of these precautions no precipitation occurs. T. A. H. Yttrium Earth related to Gadolinium. GEORGES URBAJN (Compt. rend. 1904 139 736-738).-By means of three separate methods of fractional crystallieation the author has obtained from the yttrium earths 100 grams of a rare earth which consists chiefly of the oxide of Lecoq de Boisbaudran's new element Z6 (compare Abstr. 1896 ii 249 ; also Demarqay Abstr.1900 ii 656). The methods employed were (i) Fractional crystallisation of the double nitrates of the rare earths and of nickel. The fractions containing the element Z6 were intermediate between those of gadolinium and dysprosium. (ii) Fractional crystallisation of the nitrates of the earths in the presence of bismuth nitrate (compare Abstr. 1904 ii 37,43,173 ; also Demarpy Abstr. 1900 ii 347). The nitrate of Z6 has the same solubility as bismuth nitrate. (iii) Fractional crystallisation of the ethyl sulphates of the rare earths (compare Abstr. 1900 ii 346). The emth thus separated exhibits only the absorption band X = 488 characteristic of Z6 but this does not preclude the possibility of ZS being a mixture of elements some of which possess no absorption spectra.ANTON WAEGNER (Zeit. anorg. Chew. 1904 42 118-126. Compare Abstr. 1903 ii 729).-That very varying statements have been made as to the colour of neodymium oxide Nd203 is probably due to the oxide under investigation having been in many cases contaminated with other rare earths and particularly with praseodymium. The crude neodymium chloride used by the author which con- tained traces of praseodyiniuni and lanthanum was converted into the M. A. W. Neodymium Oxide. 3-236 ABSTRACTS OF CHEMICAL PAPERS. oxalate; this when carefully heated in a platinum boat in a current of oxygen formed a pink residue from which carbon dioxide could be obtained a t a higher temperature. When the oxalate is heated a t ft bright red heat an oxide of the probable composition Nd,O is formed ; prepared in this manner it is brownish-pink and resembles Brauner’s oxide Nd,O in being converted by prolonged heating with the blowpipe or in a current of hydrogen into the oxide Nd,O,.Further its brown tint is clue to a trace of praseodymium peroxide since when heated moderately in a current of hydrogen the traces of praseodymium peroxide are reduced to sesquioxide and the true colour of the neodymium oxide namely a sky-blue colour with a violet tint is rendered evident;. The existence of a higher neodymium oxide was also rendered prob- able by the spectrometric observations with the two oxides. The spectrum from the oxide Nd,O is quite different from that of the oxide Nd,07. A. McK. Deposition of Aluminium from Ethyl Bromide Solution. HARRISON E.PATTEN (J. Physical Chern. 1904 8 548-565).-1t has been shown by Plotnikoff (Abstr. 1902 ii 639) that aluminium bromide dissolved in ethyl bromide yields a conducting solution from which aluminium may be deposited and the author has further studied this deposition. I n a 4.38 per cent. solution no aluminium was deposited even with currents of fairly high density; evidence was however obtained of the formation of protective films on the aluminium and this in a solution which was almost perfectly free from oxygen. I n a solution of 40.95 per cent. of aluminium bromide aluminium was deposited when the current density reached 0*0083 ampere per sq. em. ; the electrolytic metal reacts on the solution vigorously a gas probably butane being evolved ; below the current density given the rate of dissolution exceeds that of deposition.The potential of the aluminium against the solution was 1.10 volts and that of the bromine was - 1-20 volts. Using the aluminium as anode further evidences of film formation were obtained but no high counter-pressures were obtained. During the work aluminium bromide was obtained in the form of large rhombohedra1 crystals of a pale yellow colour. Stimulating and Paralysing Influences of certain Sub- stances in the Production of Rust. LEON LINDET (Contpt. reizd. 1904 139 S59 -862).-The catalytic action exercised by certain metals on the oxidation of organic compounds has been studied by Livache (Abstr. 1883,756 ; 1884,532) by Trillat (Abstr. 1903 i 222 ; ii 201 589 ; 1904 ii 38) and by Duchemin and Dourlen (Abstr. 1904 i 961).The author finds that the rusting of iron is accelerated by the presence of copper and retarded by such metals as tin lead zinc manganese aluminium or magnesium; the phenomena are to be attributed to the hydroxide of the metal which dissolves in the water for similar stimulating or paralysing effects are produced on the iron by water which has been in contact with the metal.. Arsenic and its compounds exercise a paralysing effect on the rusting of iron and when present in large quantities stop it altogether; in this case the dissolved L. M. J.INORGANIC CHEMTSTRY. 37 iron hydroxide forms colloidal ferrous or ferric arsenite. Soluble salts such as the chlorides and sulphates of the alkali metals have a stimulating effect on the rusting of iron probably due t o their electro- lytic dissociation whilst among organic substances such compounds as sugar phenol or resorcinol stimulate the formation of rust ; alcohol or methyl salicylate has a retarding effect and acetic or salicylic acid dissolves the iron as rapidly as it is oxidised.A. V. DUMANSKY (J. Russ. Phys. Chem Xoc. 1904 36 1067-1069).-The colloidal ferric hydroxide examined mas prepared by saturating a solution of ferric chloride with ammonium carbonate and purifying the solution obtained by dialysis. The liquids thus prepared contain as much as 5.3 grams of ferric oxide per litre but no iron ions are present; the solution also contains chlorine probably in combination with ammonia. On electrolysis or with electrolytes such as barium hydroxide potassium thiocyanate hydrochloric acid zinc sulphate &c.the solution is coagulated but with mercuric or mercurous nitrate or ferric chloride it forms first a complex colloid; besides this salts of mercury or copper convert a part of the iron into salts of their acids. By ammoniacal solution of copper oxide the colloid is precipitated together with cupric oxide whilst in the presence of organic hydroxy-acids and on heating the cupric oxide is reduced to cuprous oxide; the same occurs with ammoniacal silver oxide solution. When the solution is boiled with Fehling’s solution the colloid is precipitated together with cuprous oxide. T. H. P. Perchromic Acid and the Perchromates. HORACE G. BYERS and E. EMMET RETD (Amer. Chenz. J. 1904 32 5O3-513).-The blue compound produced when chromic acid is treated with hydrogen peroxide has been the subject of numerous investigations and various formuh have been assigned to it.Recently Patteii (Ahstr. 1903 ii 431) has stated that this substance is not perchromic acid but that the chromium is present in the chromous state. When the ethereal solution of the blue compound is treated with potassium a t - 20° hydrogen is evolved arid a purplish-black precipi- tate is produced. This compound which has the composition KCrO or K,Cr,O is unstable and rapidly decomposes with evolution of oxygen and formation of potassium dichromate. By the addition of an alcoholic solution of potassium cyanide to the blue solution Wiede (Abstr. 1S9S ii 295) obtained a similar compound to which he ascribed the formula KCr05,H202.When the blue solution is pre- pared without employing an excess of hydrogen peroxide the compound obtained on the addition of potassium cyanide has the same com- position as that produced by the action of potassium. Thc corre- sponding sodium aminoniuum Zitluiunz magnesium cuZciurn barium and zinc salts were prepared. A study of the blue ethereal solution has shown that it contains perchromic acid H,Cr,O,. When the solution is prepared in presence of an excess of hydrogen peroxide it is probable that a more highly M. A. W. Colloidal Ferric Hydroxide oxidised compound is also produced. E. G.38 ABSTRACTS OF CHEMICAL PAPERS. Perceri tage of dissolved Tempera- salt. sp. gr. ture. Derivatives of Complex Inorganic Acids. ALLEN ROGERS and Com- EDGAR F.SMITH (J. rliizer. Gltem. Soc. 1'304 26 1474-1484. pare Abstr. 1903 ii 375).-Amiuonium manganitungstate 4(NH4)20,Mn203 1 2W0,,23H20 (Brubaker Thesis 1904) prepared by boiling ammonium paratungstate and manganic hydroxide with ~1 ater forms large red octahedral crystals and is very soluble in water. Amino&m nickelitungstate 3(NH4),0,Ni,O3,l 6W03 22H2O ob- tained by boiling the hydrated sesquioxide of nickel with an am- moniacal solution of ammonium paratungstate forms a greenish-white crystalline powder and is sparingly soluble in water. On adding barium chloride to a solution of this salt ba?*iunz nickelitungstate 19BaO,Ni,O 16 WO,? is produced as a white precipitate. When ammonia is passed into the solution of ammonium nickelitungstate another ccn~nzoniun~ salt (NH4),0,Ni,0,,4 W0,,7H20 is obtained which is dark blue when moist but of a light blue colour when dry.The following compounds were prepared by boiling the respective hydroxides with an aqueous solution of ammonium paratungstate for 8 hours filtering and evaporating the filtrate to dryness on the water- bath. Ammonium prccseodymitujagstate 2 (NHJ20,Pr2O3,l 6W03,1 6H20 is obtained as a green transparent gum. and 6Ba0,Pr,0,,16W03,9H,0 form white powders. 4 Ag,0,Pr20i3 16 W0,,8H2O is of a greenish-white colour. the barium salt 6Ba0,Nd,03,16W03,17H,0 are of a pink colour. the ba&m and silver salts 5 BaO La203 16 WO 16H,O and form white powders. as a red transparent glass. When dry all the salts were quite insoluble. The bnrium salts 4Ba0,Pr20,,1 6W0,,7H20 The silver salt Ammonium neodgmitungstcde 3(NH,),0,Nd203,16W03,20H,0 and Anzmoniurn Iantl~aizitungstale 2(NH,),0,Ln,03 16 W 0 16H,O and 5Ag20,La2O3 16 WO 1 6H,O Ainnzoniunz ceritungstate 2(NH,),O,Ce,O,,l 6W03,2H,0 is obtained E.G Percentage of dissolved Tempera- salt. Sp. g c ture. 1 1.0056 14.6" 2 1.0112 16.3 3 14161 13.7 4 1.0215 13.1 5 1-0260 14.2 6 1.0313 15.2" 7 1.0366 14.3 8 1.0418 14.5 9 1.0469 15 10 1,0517 14.8 When uranyl chloride is heated in dry air it is decomposed into chlorine and the dioxide UO which is oxidised to the higher oxides UO and U,O and is similarly decomposed when heated withINOltGANIC CHEMISTRY. 39 calcium hydroxide or calcium oxide the final products being calcium uranate or a mixture of calcium uranate and diuranate [pyrouranate a] and similar results were obtained with barium or strontium oxides or hydroxides.By the action of fused potassium or sodium hydroxide uranyl chloride is converted into a mixture of the alkali chloride and diuranate [pyrouranate 't] together with a little alkali uranate ; the alkali diuranates [pyrouranates '13 are insoluble in water but soluble in dilute nitric acid. By the action of sulphuric nitric or selenic acid uranyl chloride yields uranyl sulphate nitrate or selenite respectively and it is reduced to uranous oxide UO by the action of hydrogen hydrogen sulphide zinc dust or iron filings a t a high temperature. A neutral aqueous solution of uranyl chloride gives the following qualitative reactions with potassium hydroxide an orange precipitate ; with ammonia or methylamine a yellow precipitate insoluble in excess of the reagent; with sodium hydrogen carbonate an evolution of carbon dioxide and no precipitate ; with potassium or sodium carbonate or sodium phosphate or potassium cyanide a yellow gelatinous precipitate insoluble in excess of the reagent; with ammonium sulphide a brown precipitate becoming red ; with hydrogen sulphide a slight brown precipitate after 24 hours ; with potassium ferrocyanide or ferricyanide a deep reddish-brown precipitate insoluble in excess of the reagent.M. A . W. Tin Amalgams. WILLEM J. VAN HETEREN (Zeit. nnorg. Chem. 1904 42 129-173).-1n the liquid state tin and mercury are miscible in every proportion. The points a t which such mixtures solidify rise from tin to mercury and form two curves the first from 231.6" to - 34.5" for concentrations of 100-0.3 atomic percentage of tin the second from -34-5" to - 38.6' for concentrations of 0-3-0 atomic percentage of tin.The first curve is almost a straight line until 120° when it gradually bends till 40" is reached a t which point it falls almost perpendicularly along the temperature axis. Consequently at low temperatures the amount of tin in the saturated liquid amalgams is exceedingly small. From the liquid amalgams represented by this curve either pure tin separates or tin with very little mercury. The solid phase a t 25' contained 94 per cent. of tin as determined analytically and 99 per cent. as determined by electrical means. The potential differences of amalgams of from 0.001 to 100 per cent.of tin were measured at 25" against an amalgam with 15.95 per cent. With hhe liquid amalgams the potential difference increases rapidly the higher the amount of tin until the saturation point with 1.2 per cent. of tin is reached. Contrasted with pure tin the difference is about 0.5 millivolt more. By comparison of the potential differences a t 25' and 50" respectively the deduction is made that a t 25" the conversion of 1 gram atom of tin into liquid amalgam with 0.01 to 1-00 atomic percentage of tin that is almost pure mercury involves an amount of heat equal to about 3000 calories. Amalgams containing 0.3 to 85 atomic percentage of tin exhibit at - 34.5" a transformation which with the addition of heat is accom- panied by contraction.A new solid phase results mixed crystals being40 ABSTRACTS OF CHEMICAL PAPERS. probably,produced where the tin may be supposed to exist in a form unknown in the free state Between - 34.5" and - 38.6" those mixed crystals separate and an expansion occurs which decreases when the percentage of tin is considerable and disappears with an atomic percentage of 60 to 70 of t'in. All amalgams up to 60 per cent. of tin solidify a t - 38.6". A. McK. Stannichlorides of the Types M,'SnCl and M"SnC1,. 11. EUGEN VON BIRON (J. Buss. Phys. Chem. Xoc. 1904 36 933-947. Compare Abstr. 1904 ii 567)-On repeating the experiments of Engel (Abstr. 1897 ii 376; 1898 ii 29 119) the author obtains tin meta- and para-chlorides having properties identical with the products obtained by Engel.The meta-chloride differs slightly in composition from that prepared by this author From the results obtained together with t'hose of other investigators the following conclusions are drawn. When a-stannic acid undergoes change it yields an uninterrupted series of varieties of P-stannic acid differing as regards their degree of condensation which becomes greater as the temperature rises. The action of hydrochloric acid on these various p-stannic acids gives rise to oxychlorides which have an indefinite composition and contain a larger or smaller proportion of chlorine according as the condensation of the P-acid is small or great. The oxychlorides differing considerably in composition exhibit differences in properties similar to those shown by the tin meta- and para-chlorides of Engel. The reverse reactions by which the oxychlorides are converted into a derivative of the a-acid namely stannic chloride proceed the more readily the less the condensation.T. H. P. Stannates. ITALO BELLUCCI and N. PARRAVANO (Atti R. Accad. Lincei 1904 [v] 13 ii 339-346. Compare Abstr. 1904 ii 823). -Lead stannate PbSn(OHj is obtained as a white amorphous precipitate and loses 3H,O on heating to redness. The barium ( + 4H,O) calcium and strontium salts were also prepared and analysed. All these salts are of the type X'Sn(OH) and contain a far more stable complex than the stannichlorides (see Abstr. 1904 ii 822). This greater stability of the stannates is borne out by conductivity measurements of solutions of potassium stannate. T. H P.Titanium. I. Hydrates of Titanium Trihaloids. ARTHUR STAHLER (Ber. 1904 37 4405-4410).-The author was unable to obtain the green compound TiC1,,4H20 described by Glatzel (this Journal 1877 i 688). Tit3 nium trichloride hexahydrate TiC1,,6H20 prepared by the elect,rolytic reduction of the tetrachloride is violet Titanium rubidium chloride TiCI 2RbUl,H,O prepared by passing hydrogen chloride into an aqueous solution of a mixture of rubidium and titanium chlorides which was heated on the water-bath is green andINORGANIC CHEMISTRY 41 forms a violet solution with water. Titanium cesium chloride TiC1,2CsC1,H20 is green. TiBr,,GH,O prepared by the electrolytic reduction of titanium tetrabromide is violet and more unstable than the corresponding chloride. Titanium tri-iodide hezahydrate TiI,,6H20 prepared by the electrolytic reduction of titanium tetraiodide is violet and very unstable. Titanium tribromide hexahydrate A.McK. Zirconium Salts. Constitution of Normal Zirconium Sul- phate. RTJDOLF RUER (Zeit. cinorg. Chem. 1904 42 87-99).- Normal zirconium sulphate does not give the chai.itcteristic reactions with oxalic acid and ammonium oxalate respectively such as the chloride gives These reactions do not take place with solutions of zirconium oxychloride to which normal ammonium sulphate or sodium sulphate is added. The conclusion is drawn accordingly that zir- conium sulphate in aqueous solution is constitutionally different from zirconium chloride or nitrate; its behaviour in aqueous solution is best expressed by formulating it as ZrOS0,,H,S04.Since this compouLd is represented as a dibasic acid i t forms sodium and ammonium salts of the type ZrOSO,,SO,M the complete electrolytic dissociation of which is represented by ZrOS04,M2S0 = ZrOSO,,SO," + 2M" zirconium being present in the complex anion. The constitution of crystalline zirconium sulphate is very probably ZrOS0,,H2S0,,3H,0 and not Zr( S0,)2,4H20. Complex formation with concentrated solutions of sodium salts such as sodium chloride and sodium nitrate was also noted. I n such complex salts the zirconium is present in the cathion. Zirconium oxgchloride in aqueous solution is gradually decomposed when left at the ordinary temperature or when heated. A. McK. Red Derivatives of Hydrated Vanadium Trichloride. ARTHUR STAHLER (Ber.1904 37 441 1-441 2).- Vccnadiuna rubidium chloride VdC1,Rb2,H20 prepared by evaporating a solution of hydrated vanadium chloride saturated with hydrogen chloride forms a red crystalline powder which is sparingly soluble in water. Similar anamonium potussiuna and c ~ s i u n ~ compounds were obtained ; the magnesium compound has the composition VdCl,hlg,H,O. These substances are probably analogous to the chromium derivative CrC1,(OH,)Rb2 (Werner and Gubser Abstr. 1901 ii 453). W. A. D. Purification of Sodium Vanadate Liquors ; the Processes of Double Decomposition for the Industrial Separation of Metals. H. HERRENSCHMIDT (Compt. rend. 1904 139 862 -864).- I n the separation of vauadic acid from the mixture of sodium vanadate and silicate (compare Abstr. 1904 ii 824) the use of sulphuric acid is to be avoided as it necessitates a concentration of the liquors introduces a third substance namely sodium sulphate which has to be removed and precipitates the vanadic acid with the silica whereas the addition of a slight excess of vanatlic acid t o the dilute42 ABSTRACTS OF CHEMICAL PAPERS.solution of sodium vanadate and silicate causes the complete pre- cipitation of the silica the vanadic acid remaining in solution. I n all cases of separation of metals the author recommends the use as a reagent of a compound cf one of the metals already present; thus the separation of iron from manganese is effected by the carbonate or sesquioxide of manganese according to the state of oxidation of the metals in solution. 31. A. W.Preparation of Aurous Iodide by the Action of Iodine on Gold. FERNAND MEYER (Cowzpt. rend. 1904 139 733-736).- Pure dry iodine has no action on gold a t the ordinary temperature but combines with it to form green amorphous aurous iodide AuI at temperatures between 50' and the melting point of iodine ; a t higher temperatures the iodide is obtained in the form of lemon-yellow crys- talline plates but the reaction is reversible and at 190" the iodide is completely decomposed into iodine and gold. I n order to free aurous iodide from uncombined iodine it is heated a t 30" whereby the latter is volatilised it being impossible t o employ any solvent for this purpose as alcohol ether chloroform or benzene decomposes the iodide. I n the presence of water in a closed vessel iodine reacts with gold to form aurous iodide provided the iodine is in excess. M.A. W. Volatilisation of Platinum. GEORGE A. HULETT and H. W. BERGER (J. Amer. Chem. Xoc. 1904 B 1512-1515).-An account is given of a series of experiments carried out with the object of deter- mining the conditions under which platinum is volatilised. A large sheet of platinum foil was heated by means of an electric furnace and the loss in weight determined a t intervals. I n order to ascertain whether the volatilisation was influenced by the impurities present some experiments were made with a specimen of platinum of a high degree of purity; the results showed that the pure platinum behaved in the same way as the foil. Platinum begins t o volatilise in air a t a temperature of about 800" and the rate of loss increases rapidly as the temperature rises. No volatil- isation occurs when the metal is heated in the absence of oxygen and it is suggested therefore that a t high temperatures the platinum is converted into a volatile oxide which undergoes decomposition a t temperatures below SOOO. E. G. Absorption of Hydrogen by Rhodium. L. QUENNESSEN (Compt. rend. 1904 130 795-796).-Wilm's statement (A bstr. 1881 514) that hydrogen is more readily absorbed by rhodium than by palladium is contradicted. Rhodium was purified by heating it with sodium chloride in a current of chlorine dissolving the product in water con- verting into sodium rhodium nitrite and crystallising the latter. The metal regenerated from this does not absorb a measurable amount of hydrogen when heated and cooled in a current of the gas. It acts as a catalyser in promoting the union of hydrogen and oxygen. H. M. D.1\IINERALOGICA4L CHEMISTRY. 43 IricEium Smquisulphate and its Aluma LUIGI MARINO (Zed. ccnoiy. CizRnt,. 1904 32 213-224. Compare Abstr. 1903 ii 376).- Iridium sesquisdphate Ir,(SO,),,xH,O j s prepared by crystallisation from a solution of the hydrated sesquioxide in dilute sulphuric acid in the absence of air. Iridium ccesizcnz aZum Ir,(SO4),,Cs,SO4,2-fH20 separates in regular octahsdra crystallographic measurements of which are quoted. Its aqueous solution is yellow and becomes pink when warmed above 40'. It melts a t 109-110" to a yellowish-red liquid. Iridium rubidium alum (Zoc. cit.) is less solubIe than t,he caesium alum; it melts at 108-109" t o a yellowish-red liquid. Iridium potassium ult~m Ir,(S04),,K2S0 24I'i,O forms yellow octa- hedra and melts at 102-103'. Iridium a~nmonium ccZunz Ir2(S0,)3,(NH4)2S04,24H,0 forms yellow- ish-red octahedra and melts at 105-106" t o a reddish-violet liquid. When it is heated a t a red heat iridium is formed. Iridiurq thalliurn alum Irg( SO,),,T1,SO4,24H,O forms golden-yellow octaheara. A. McR.