INORGANIC CHEMISTRY. Inorganic Chemistry. ii. 23 The Determination of the Molecular Complexity of Liquid Sulphur. ALEX. MITCHELL KELLAS (T. 1918 113 Occurrence of Hydrogen Selenide in Rain and Snow. Y. KARRZR (Helv. C‘hirn. Acta 1918 1 499).-Repetition of Gass- mann’s experiments (A. 1918 ii 309) has led the author to the conclusion that selenium is not present in snow or rain. Starting and Stability Phenomena of the Oxidation of Ammonia and Similar Reactions. F. G. LILJENROTH (CJzewz. mill M e t . Enq. 1918 19 287-293).-Conversion curves have been plotted for the oxidation of ammonia a t various temperatures showing that whilst little oxidation takes place a t 400° it rises rapidly between 450° and 500° t o nearly loo% reaches a maximum a t about 750° and then decreases first slowly and afterwards rapidly.The temperature of the gauze or catalyst may also be plotted for various percentages of ammonia-oxidation and the curve is found to be a straight line the position of the line termed the “ heat of reaction line,” on the conversion curve diagram depending on (1) the initial temperature of the gas and (2) the initial composition of the gas. The effects of changes in the velocity and the composition of the gaseous mixture on the relative positions of these two curves are described and the conditions for (1) the cessation of the reaction (2) overcoming the prejudicial effects of catalytic poisons are indicated. The reaction does not start spontaneously but must be initiated by heating to a particular ignition temperature which is below the reaction temperature.The use of oxygen is shown to be not justified as it merely results in a higher temperature necessitating water cooling of the gauze. A cheap low-grade catalyst may be possible for the first gauze and a platinum gauze for completion of the oxidation in a manner analogous to the sulpliuric acid process. The synthetic ammonia process is also considered and it is shown that in this case a heat exchanger must always be used and additional heat must usually be supplied. With a high pressure and a good catalyst however no heat need be supplied except during the starting period. 903-922). H. JV. B. N. The Oxidation and Ignition of Coal. RICHARD VERNON WHEELER (T. 1918 113 945-955). Oxidation of Carbon Monoxide in Contact with Copper. K.A. HOFMANN (Ber. 1918 51 1334-1346).-Continuing his search for a reagent. t o oxidise carbon monoxide a t the ordinary temperature (A. 1916 ii 637) t.he author has shown that hydratedii. 24 ABSTRACTS OF CHEMICAL PAPERS. copper oxide in the presence of aqueous alkali converts carbon mon- oxide into a carbonate although a t only a slow rate. The addition of platinum metals especially iridium increases the rate five times. In contact with metalh copper moistened with aqueous alkali carbon monoxide mixed with air is oxidised two or three times more rapidly than it is when in contact with a copper oxide surface of the same area. The copper is converted into a peroxide Cu20 or CuO which is the real oxidising agent. The addition of a trace of iridium to the copper does not change the oxidising power of the peroxide but increases the adsorptive capacity of the surface for carbon monoxide and thus increases the rate of oxidation.It is very remarkable that the rate of oxidation of hydrogen in contact with an alkaline copper surface is only 1/70 (with addition of iridium 1/50) of that of carbon monoxide the copper surface having a very small capacity of adsorbing molecular hydrogen. The experiments were performed in a Hempel gas pipette filled with rolls of copper gauze moistened with 15% potassium hydroxide sdu- tion. The concentration of the alkali does not appreciably affect the results. c. s. WILLTAM NORMAN RAE (T. 1918 113 880-884). The Action of Chlorine on the Alkali Iodides. Literature on the Solubility of Systems Relating to Nitre Cake.H. W. FOOTE (J. Ind. Eizg. Ch,em. 1918 10 896-897).-A resume of the literature dealing with the solubility relationships of the systems Na,S'0,-H,S04-H,0 ; Na,SO,-RSO,- H,O; and RS04-€3,S0,-H20 (R=Fe" Cu Ra Ca G1 etc.). J. F. S. Recrystallisation of Nitre Cake. BLAIR SAXTON (J. h2d. Eng. Chem. 1918 10 897-901).-Equations based on solubility deter- minations have been developed by means of which the amount of any one solid phase that can be separated from the Bystem Na,S04-H,S04-H,0 can be calculated if the composition of the original nitre cake and the acid concentration after crystallisation are known. These equations are for the temperature 25O. Further equations are given for the same temperature by means of which the amount of water t o be added to the nitre cake may be calcu- lated in order t o leave a calculated amount of one of the solid phases. Further equations for obtaining the maximum amount of each solid phase from solution a t temperatures of Oo and 2 5 O are also given.Leaching processes are outlined by means of which sulphuric acid may be concentrated in the solution and sodium d p h a t e in the solid. It is found experimentally that this separa- tion can be carried out more efficiently a t Oo than a t 25O. J. F. S. Colloidal Silver. ALWYN PICKLES (Chem. News 1918,117 358). -When well-washed silver oxide is reduced by a rapidly stirred 50% solution of formaldehyde a solution of colloidal silver is pro- Xuced. This solution is very stable and varies in colour from paleINORGANIC CHEMISTRY.ii. 25 lilac to rich ruby-red. Acetaldehyde has not the same effect and with formaldehyde t.he coloured solutions are only produced at about 3 5 O . The colour is discharged slowly by salt solutions and by nitric acid. Hydrogen peroxide is slowly decomposed by the solution. J. F. S. Rational Preparation of Superphosphates. A. AITA ( ~ ~ d i Glhim. AppZ. 1918 10 45-103) .-On dissolving increasing quantities of monocalcium phosphate in a given weight of water a t constant temperature the proportion of free phosphoric acid con- tinually increases and tends towards a limit in accordance with the equation 2CaH4(P04)2 t CaH4(P0& + CaHP0 + HSPOk. Up to the saturation point a t 1 5 O there would thus be a liquid phase conslmug 01 water monocalcium phosphate and free phosphoric BCICL auu a Solid phase comlsting solely of dicalcium phosphate lormea by hydrolysis or the monocalciuni phosphate.Beyond the saturation point with increasing quantities ot calcium made and phosphoric oxlde the liquid phase remains unaltered whilst the solia phase is constantly enricned by monocalcium phosphate. On raising the temperature the decomposition of the monocalcium phos- pnate is accentuated w h i s t the saLuration point is retarded. hiono- calcium phosphate appears in the solid phase at the same limit of concentration i o r the calcium oxide but a t a greater concentration 01 the phosphoric omde. I n the case of. commercial superphosphates containing about li2-20% of soluble phosphoric oxide and lU-2U% 01 water there is a system with a fairly hgh proportion of phos- phoric oxide and a very low proportion of water.In estimating nee phosphoric acid in such products it is necessary to use anhy- drous ether for the extraction since water alcohol or ordinary ether cause more or less hydrolysis of the monocalcium phosphate according to the amount ot water originally present. The physico- mechanical properties of superphosphates depend on the proportion oE free phosphoric acid and water the former depending on the nature and physical conditions of the components of the reaction and the latter mainly on the concentration of the sulphuric acid used in the preparation. On these grounds commercial superphos- phates may be classified as normal or abnormal products the former containing not more than lO-li?% of water or 1-2% of phosphoric oxide as free phosphoric acid (about '5-10% of the total soluble phosphoric oxide).Dicalcium phosphate is invariably present and the fraction of phosphoric oxide in that form of combmation should be equal to that present as free phosphoric acid. The mono- and dicalcium phosphates and calcium sulphate are mainly present in the hydrated form. In the case of superphospliates of abnormal constitution the water of the liquid phase exceeds 12% and the free phosphoric acid exceeds 2% o r 10% of the soluble phmphoric oxide whilst the salts are mainIy in the crystalline condition and there is little or no dicalcium phosphate present. It is commonlyii. 26 ABSTRACTS OF CHEMICAL PAPERS. accepted in accordance with Kollb’s view that the reaction between sulphuric acid and mineral phosphates takes place in two stages 3Ca,(PO,) + GH,SO = 4H,PO + Ca3(P0,) + GCaSO but the observed facts show that the main reaction is more correctly represented by the equation 5Ca,(P04) + 11H,SO = 4CaH,(PO,) + 2H,PO + 11CaS0,.The infiuence of raising the temperature on the reaction is to increase the concentration of free phosphoric acid in the liquid phase whilst in the solid phase the dicalcium phosphate increases in equal proportion with the free phosphoric acid. !!?hem constitu- ents gradually interact to form monocalcium phosphate so that the existence of dicalcium phosphate in an industrial product will (1 epend on the proportion of free phosphoric acid originally present. Hence in products prepared with an excessive quantity of sulphuric acid and thus containing a high proportion of free phosphoric acid the dicalcium phosphate will be reduced or disappear altogether.I n fact monocalcium phosphate is not hydrolysed in presence of an excess of phosphoric acid and in such cases the solid phase of the system will consist solely of monocalcium phosphate. The applica- tion of these principles to the industrial preparation of superphos- phates yields products with the desired physico-mechanical proper- ties. Ca,(P0,),+4H,P0,=3CaH4(P0,) [See also ,7. SOC. Phem. Znd. 1919 33tl.l C . A. M. The Decomposition of Barium Peroxide and the Re- activity of the Resulting Barium Oxide. J. A 4 ~ ~ ~ HEDYALL (Zeitsch. auorg. Chem. 1.918 104 163-168).-The decomposition of barium peroxide by heat a t atmospheric pressure has been fol- lowed by means of the heating curve.The peroxide was heated in a carbon tube furnace and the temperature recorded a t 10 sec. intervals by means of a platinum-platinum-rhodium thermo- element. The reaction being endothermic its range is indicated on the heating curve by a pronounced flattening towards the time axis. The temperature a t which the vapour pressure of the evolved oxygen is equal to 760 mm. was found to be 795O. This agrees with the value 796O found by Le Chatelier. The higher temperature 825O obtained by Eildebrnnd is accounted for by the fact that this observer used very carefully dried materials,.for in the absence of moisture the reaction is verv slow and incompIete. I n presence of copper oxide barium peroxide starts to decompose a t about 200° the reaction becoming most vigorous a t 625-660°.a? shown by the heating curve. When the wroxide is heated with amorphous silica. however the rate of rise of temperature increases above 400O. The endothermic decomposition of the peroxide is evidently accompanied by a more strongly exothermic reaction probably the formation of a barium silicate; brought about by the ereat reactivity of the barium oxide a t the moment of its forma- tion. Even when powdered quartz glass or crushed quartz is usedINORGANIC CHEMISTRY. ii. 27 in place of arnorphoiis silica there is evidence in the heating curve of silicate formation. E. H. R. Solubilitv of Cupric Hydroxide to a Certain Concentra- tion in Sodium Hydroxide and Potassium Hydroxide. En.JUSTIN-MUELLER (Compt. rend. 1918 167 779-780) .-Cu~ric hydroxide dissolves in aqueous sodium hvdroxide (D 1*345-1*370) or aqueous potassium hydroxide (D 1*453-1*498) to the extent of 0.78 gram in 100 c.c. giving bright *blue solutions which do not qive any precipitate when boiled directlv or first diluted and then boiled. Solutions prepared with more dilute alkali are not stable. W. G. Scandium from a Brazilian Source. C. JAMES (J. Amer. Chem. Soc. 1918 40 1674).-Whilst working up quantities of Brazilian zirconia the author obtained a gelatinous residue which on examination was shown to consist of scandium fluoride. J. F. S. Rare Earths. VIII. Separation of Yttrium from Erbium ; The Ratio Er,O 2ErC1,. EDWARD WTCHERS R. S. HOPKINR. and C.W. BATXE ( J . Amer. Chem. Soc. 1918 40 1615-1619. Compare A . 1917 ii 34).-Using material containing only erbium and vttrium the authors have investigated the newer methods pro- posed f o r the separation of these two elements. The cobalticyanide and the nitrite precipitation methods were found to give good results the latter being the more efficient and practicable. The older nitrate fusion method was found to give results far superior to the other methods and bv this method erbium compounds of a hiph degree of purity were ohtained. The ratio of erbium oxide t o erbium chloride was determined in seven analyses. The ratio was found to vary with the temperature and length of time of ipnition of the oxide. Erbium oxide prepared bv the ipnition of the oxalate and ignited for several hours a t 800° and two hours a t 900° was found to retain considerable amounts of carbon dioxide This is contrary to Hofmann’s results (A.1910 ii 1073). and con- sequently brings into disrepute the Present accepted value of the atomic weight of erbium. Until erbium oxide of the definite com- position Er,O is prepared no ratio in which the-oxide is one term can be trustworthy for the purpose of atomic weight determivations. J. F. S. Preparation and Properties of Yttrium Mixed Metal. .T. F. G. HICKS (J. Amer. Chem. SOC. 1918 40 1619-1626).- Experiments of a preliminary nature dealing with the preDaration of vttrium mixed metal are described. It is shown that the method of preparing anhydrous chlorides of the metals of the yttrium earths by heating the hydrated chlorides with ammonium chloride t o drive off five of the six molecules of water of crystal- lisation and then in a current of hydrogen chloride to remove theii.28 ABSTRACTS OF CHEMICAL PAPERS. last molecule of water is capable of being used on the large scale. The mixed metal has been prepared in the form of powder by heating the anhydrous chlorides with sodium in a vacuum a t llOOo and also by electrolysing a mixture of the molten chlorides in a protected graphite crucible using a graphite anode. Electro- lysis of a solution of the mixed oxides in fused cryolite also yields the mixed metal in the form of powder but the method is less efficient than the foregoing methods. I n all these processes there is considerable loss of yttrium chloride owing to its volatility a t t.he temperature of the experiments.The powdered products have been obtained in a coherent form by sintering in a vacuum but the resulting mass easily disintegrates. The product obtained has a mean “atomic weight” of 120 and contains 94*05-95*70% of metal which corresponds with 37.5% of yttrium. It burns in the air a t a dull red heatl with a very bright light and yields a light brown oxide. It is slowly oxidised by moist air a t the ordinary temperature. It glows when heated in hydrogen nitrogen or carbon dioxide. It does not amalgamate with mercury and is readily attacked by water. Yttrium mixed metal is pvronhoric but not so strongly as the cerium metal iron alloys. Effects of Heat on Chemical Glassware. R. G. SHERWOOD ( J .Amer. Chem. Soc. 1918 40 1645-1653}.-When glass is heated there is shown to be evidence of two distinct kinds of gaseous evolution that resulting from adsorbed material which is readily removed at temperatures below 300° and that resulting in all probability from a decomposition of t.he glass itself. The latter effect; becomes importantl above 400° for the softer glasses and above 500* for the harder glasses. There is some evidence of a definite characteristic rate of gaseous evolution for each tempera- ture to which glass is subjected. increasiny with the temperature and extending over a considerable period. Observations on one sample a t 500° showed a small continuous evolution even after heating for twenty hours. Adsorption products are confined t o quantities which ar0 represented approximately by a layer of gas about one molecule deep and are removed with much greater rapidity a t lower temperatures than the other products obtained.which are due to the heating of the glass. The most important of the gaseoiis evolution products obtained from glass under the influence of heat-is water. which as the temperature is raised to the softening point of the glass constitutes almost the entire quantity of the evolution but its amount a t a lower temperature may be relatively unimportant,. Plasticity and ‘Strength’ of Clay. OTTO KOLTE (3ied. Zentr. 1918 47 108-109).-Extraction of a heavy Silesian clay with alcohol and ether did not cause any diminution in the plas- ticity or ‘strength’ of the clay. The presence of a certain pro- portion of organic matter therefore does not affect.these qualities of the clay. The extract was found to contain sulphur and an organic compound which was not identified. J. F. S. J. F. S. H. W. €3.INORGANIC CHEMISTRY. ii. 29 Zirconyl Basic Chromate. F. P. VENABLE and L. V. GILES (e7. ,4n~er. Ghem. Soc. 1918 40 1653-1656).-A basic zirconium chromate is prepared as a granular yellow precipitate by dissolv- ing zirconium hydroxide in a boiling solution of chromic acid diluting and again boiling the solution. The compound obtained loses a considerable quantity of its water a t l l O o but the whole of it is only lost a t 200O. The compound is shown to have the formula 2Zr0( OH)2,ZrOCr0,.8H,0 and it is suggested that its formation occurs as follows first normal zirconium chromate is formed which is immediately hydrolysed to ZrOCrO ; some of the zirconium hydroxide is partly dehydrated to give ZrO(OH),. These two substances then combine t o give the yellow insoluble compound described above.The present work is a t variance with earlier work on zirconium basic chromates by s a b e r (A. 1897 ii 295). J. F. S. Antimonic Acids and Antimonates. GEBHARDT JANDER (Ko7loid Zeitsch. 1918 23 122-144).-Analyses of the various hydrates of antimony pentoxide have been made and the dehydra- tion curves of these compounds obtained by keeping them over sulphuric acid in a desiccator. The behaviour of the anthonic acids toward hydrochloric and sulphuric acids and toward solutions of potassium and sodium hydroxides has been studied. The potassium and sodium salts of these acids have also been investi- gated. The experiments show that tlhe properties of the antimonic acids vary with the method of preparation and with previous treat- ment.Thus modifications which differ in their water content stability solubility and their behaviorir towards acids and alkalis are obtained (i) by the action of water on the pentachloride (ii) by the action of acids on antimonates and (iii) by the hydro- lysis of the trichloride in the presence of nitric acid. These varie- ties of antimonic acid differ only slightly from one another and probably as in the case of the stannic acids the difference is due to a difference in the size of tihe particles. The experiments indicate that the tri- and tetra-antimonic acids that is the soluble antimonic acids are hydrosols of small stability and that the definite hydrates of antimony pentoxide known as ortho pyro- and meta-antimonic acid can have no free existence.The hydrates of antimony pentoxide exhibitl a marked selective absorption towards dilute alkalis. Thereby are formed amorphous subthances which apparently are alkali antimonates. The composition of these substances however varies continuously with the composition of the solid hydra€e. I n concentrated alkali solutions the hydrates of antimony pentaxide dissolve and from these solutions at low temperature and by careful evaporation. various alkali antimonat.es may be crystallised hiit the nature of the salt depends on the con- centration of the mother liquor. 1-71K,0,Sb20,,8R,0 has been obtained in this way.The compound J. F. S.ii. 30 ABSTRACTS OF CHEMICAL PAPERS. Bismuth Hydride. FRITZ PmEm (Zeitsch. Elektrochem. 1915 24 298-299).-Working from the point of view that isotopes and their compounds are identical the author is of the opinion that bismuth hydride is capable of existence and that it is gaseous and only moderately stable much less so than antimony hydride. These statements are based on the fact that by the action of hydro- chloric acid on magnesium which has been covered with thorium-C (an isotope of bismuth) a radioactive hydride IS produced which has the properties enumerated above. Hydroxylamine Platinum Bases. LEO ALEXANDROWITSCIF TSCHUGAEV and ILJA ILJITSCH TSCHERNJAEV (T. 1918 113 J. F. S. 384-897). Mineralogical Chemistry. ' Hydromagnocalcite " from the Tatra Mountains Car- pathians EMANUEL GLATZEL (Centr. Mzm. 19lS 307-31 l).- The compact chalk-white material with conchoidal fracture is found as loose blocks in the Lopusna valley near the village of Liicsivna on the southern slopes of the Tatra Mountains. Analysis gave results approximating t o the formula CaCO,+ Mg(OH),. CsO. MgO. co,. HeO. Total. Sp. gr. 36-55 23.15 28.75 10.60 99.05 2-412 [This is evidently pencatite which was long ago proved to be a mechanical mixture of calcite and brucite (Mg[OH],) .] L. J. S .