INORGANIC CHEMISTRY. In or g a, n i c C h e m i 8 t F y. 31 Hydrates of Hydrogen Iodide. By S. U. PICKERING (Ber., 26, 2307-2310).--In continuation of his previous work on the hydrates OP hydrogen chloride (Proc., 1893, 45) and of hydrogen bromide (PhiE. Mug., 1893), the author has succeeded in isolating three12 ABSTRACTS OF OHEMICAL PAPERP. 0.135 0.176 0.192 0.199 hydrates of hydrogen iodide. The dihydrufe, HT.2H20, form# large crystals melting at about -43". The trihydrate, H1,3H20, melts at -48", and forms small, granular crystals. The tetrahydrate, H1,4Hz0, melts at -36*5", and is deposited in large, transparent, granular crystals. The numerical results are tabulated, and are also represented graphically in the form of curves. The following hydrates of hydrogen chloride and of hydrogen bromide a1.e known.HCI,H,O; RCl,BH,O, m. p. -1T.4"; HCl,3H20, m. p. -24.8"; HBr,H20; HBr,2H20, m. p: - 1 1 . 2 O ; HBr.3H20, m. p. -48"; HBr,4Hz0, m. p. -55.8". No simple relativnship appears to exist between the melting points of the various hydrates of the three acids. J. B. T . Decomposition of Hydrogen Iodide by Heat. Ry M. BODEEN- STEIN (Bey., 26, 2603-261 1 ; compare Abstr., 1893, ii, 369) .-Further experiments have yielded the following numbers for the amount of hydrogen iodide decomposed at various temperatures. 290" 310" 320" 340" 350" 394" 448O 518" 0.164 0.167 0.160 0.172 0.176 0.196 0.214 0.236 0.202 0'225 0.214 0236 0'262 0.241 0-231 0*2M A minimum apperrrs to exist at 320", at which temperature the Theinfluence of pressure is seen in the following table.heat of reaction is probably zero. 0 - 5 1 -0 1 -5 2.0 Pressure in atmoephercs. I 350". 1 448". I 5185 0.0000345 0 -00266 0 *ooooti99 0 *00603 0 .ooollFil 0 '00820 0 0031571 0 -01143 0 -5 1 *o 1 -5 2 -0 The constant C of the velocity equation for the decomposition varies as follows. Pressure. I 350". 1 448". I---l--- -- This table shows that the constant is very nearly proportional to the pressure. J. W. Action of Ammonia on some Peroxides. By 0. MICHEL and E. GRANDMOUGIN (Bey., 26,2565-2568,~- When dry gaseous ammonia is passed over the heated peroxides of sodium, barium, manganese, and lead, the ammonia is oxidised to nitrogen, and the metal left eitherI X <)RQANIO OHEMISTRP. 13 as hydroxide (sodinm and bsrium) or oxide (manganese sesquioxide, litharge).I n addition to these products, in all cases except that of barium, a small amount of nitrous and nitric acids is formed. A. H. Properties and Constitution of Hydroxylamine and its Homologues. By W. BRCHL (Bey., 26, 2508-2520). See this vol., i, 9. Preparation of Nitrous Oxide. By W. SMITH (J. SOC. Chem. Ind., 11, 867-869 ; 12, 10-ll).-A mixture of ammonium sulphate and sodium nitrate, kept at 215" for 2-3 hours, undergoes, in great part, decomposition into sodium sulphate and ammonium n'trate. If, how- ever, i t is rapidly raised to a higher temperature, nitrous oxide begins to be evolved at 230", and comes off with some rapidity at 24O-250". Diiring the heating up a little ammonia is evolved,and the longer the mixture is kept at about 220--230", the more ammonia is lost.If, then, tbe two salts have been mixed in molecular proportions, the deficiency in the ammonia leads t o the evolution of some of the higher oxides of nitrogen towards the end of the reaction. This may be remedied by increasing the proportion of ammonium sulphate, the mixtuve, with an additional 5 per cent. of that salt, affording a larger yield of nitrous oxide than would be obtained from the equivalent quantity of ammonium nitrate. The gas is evolved with regularity, whereas ammonium nitrate, raised to 240",, decomposes with a rapidity accelerating towards explosive violence. M. J. S. Hyponitrous acid. By A. THEM (Monatsh., 14, 294-3lO).-The author supports the theory of Dun<tan and Dymond (Trans., 1887, 636), according.to which, the f i r s t pi-odpct of the rednction of sodium nitrite in alkaline solution is the sodium derivative of a dilrydroxyl- arnine, two-molecules of which then condense t o form sodium hvponitrite, (I) Na2 + 2H20 + NaNU, = NaN(OH), + 2NaOH. (2) 2NaN(OH), = Na2N,02 + 2H20. This condensation seems to he favoured by the presence of an excess of alkali, for i f this be neutralised by a current of carbonic anhydride, no hyponitrite is fornieti. The-nitrogen evolved during the reduction is not due to the reduction of hydroxylamine, to which i t has usually been ascribed, for this substance is scarcely attacked by sodium amalgam, but prob- ably to a renction between the dihydroxylamine and hydroxylartrine, KH,.OH + NH(OH), = N2 + 3H20. The prepnration of hypo- nitrites by means of ferrous hydroxide has no advantage over the ordinary method of reduction by means of sodium amalgam.Hyponitrous acid is also formed by the action of hydroxylamine on nitrous acid. About 2 per cent. of the th?oretical amount of the silver salt is formed when equivalent solutious of hjdroxylamine hydrochloride or sulphate and sodium nitrite are mixed, allowed to remain until the violent evolution of nitrous oxide has ceased, and then treated with a solution of silver nitrate. No hyponitrite is formed in alkaline solution. Further investigatious are in progress its to the exact course of this reaction. Attempts to isolate hypo- nitrous acid from the dry silver salt by means of dry hydrogen14 IBSTRACTS OF OEEMIGAL PAPERS. sulphide showed that even at, low temperatures i t is very unstable and liable to explosive decomposition ; the remaining experiments were, tlierefore, made with solutions of the acid, prepared by act- i n g on the silver salt with tbe calculated amount oE hydrochloric acid.The solution is coloai*less and strongly acid, and is stable towards dilute acids and alkalis even on boiling. On tihation with potash, in the presence of phenolphthalein or litmus, the solution remains acid until the acid salt is formed, and then becomes alkaline. The acid does not affect methyl-orange, and does not expel carbonic anhydride from the alkali caibonntes. I n acid solution, i t is quan- titatively converted by potassium permsngannte into nitric acid, whilst in alkaline solution, nitrous acid is formed.Pure solutions of the acid, contrary to the statements of Divers on the one hand, and Van der Plasts on the other, do not decolorise solutions of iodine and prevent the formation of iodide of starch, neither do they liberate iodine from acid solutions of potassium iodide. Hyponitrous acid is very stable towards reducing agents, both in the presence of acids and alkalis. Solutions of the acid hyponitriteq of the alkalis give pre- cipitates with the salts of many metals. These metallic salts are being further examined. The Oxidation of Eydroxy1arnine.-When hydroxylamine is acted on by alkaline permanganate, an amount of oxygen is taken up which is exactly half way hetween the amounts required to convert the hydroxylamine into hyponitrous acid on the one hand, and nitrous acid on the other.This corresponds with the formation of a sub- stance of the formula H?N203, which bears the same relation to hypo- nitrous acid that an azoxy- does to an azo-compound, HO*N:N*OH. N*OH O < k O H ' Hyponitrous acid (azohydroxyl). Azoxyhydroxyl. Experiments are in progress on the isolation of this substance. Hydroxylamine is also oxidised by mercuric oxide, cupric oxide, hydrogen peroxide, and alkaline potassium ferricyanide, small amounts of hyponitrite being formed in each case. The greater part of the nitrogen, however, is converted into nitrous oxide or nitrous acid. [The paper by W. Wislicenns (Abstr., 1893, ii, 311) in which the formation of hyponitrous acid by the interaction of hydroxylamine, and nitrous acid is described was read at a somewhat later date than the foregoing.] A.H. Rate of Oxidation of Hydrogen Phosphide. By H. J. VAN DE STADT (Beit. physikal. Chem., 12, 322-%2).--When dry gaseous hydrogen phosphide and oxygen are brought together a t a low pies- sure, they combine at once with emission of light to form phosphorous acid according to the equation ZPH3 + 302 = 2H3P0,. The appa- ratus used by the auhhor to determine the combining proportions consisted of a pear-shaped bulb connected on the one hand with an air-pump and manometer, and on the other with a gas pipette, by means of which definite quantities of gas could be introduced. The A. H.IKORGANIC CHKMlSTKY. I5 From p. 15.60 13-71 14-73 bulb was rendered vacuous, a certain number of measures of hydrogen phosphide admitted, and then oxygen, measure by measure, until the fldsh on combination no longer appeared.The manometer shQwed 110 change of pressure before and after the reaction. When the gases were admitted very slowly from the pipette, an intermittent greenish- blue light was observed, and the manorneter indicated that equal volumes of oxygen and hydrogen phosphide interacted, leaving an equal volume of a permanent gas as residue. When the mixing of the two gases was allowed to take place bv diffusion at, a pressure under 50 inm., accurate results were obtained, and the crystalline solid which was deposited on the walls of the bulb was proved to be metaphosphorous acid, formed according to the equation PH3 + 0, = H2 + HP02. The crystals melt above SO", and deliquesce in presence of a little water vapour, the solution shortly afterwards becoming solid again from formation of ortho- phosphorous acid.Slow oxidation ah greater pressures appears to proceed approxi- mately according to the equ:rtion 4PH3 + -50, = 2EIP02 + BH3P03 + 2H2. Dilution does not increase the rate of oxidation con- tinuously, but, when a certain low pressure is reached, explosion takes place suddenly. The limiting pressure for explosion depends very greatly on the amount of moisture present, which, in this case, retards and prevents the oxidation, a result in direct contrast with those obtained by Baker and by Dixon for most cases of combination. By G. CARRARA (Gazzetta, 23, ii, 12-1i).-By means of cryoscopic detertiiinations in benzene solution, the author confirms the generally accepted view that the polymeride of tlziocarbonyl chloride has the molecular composition (CSCl,), ; the thermometric depressions indicate a small but increas- ing amount of dimxiation as the solutions become more dilute.The refraction constants of thiocarbonyl chloride, of its polymeride and of perchloromethylmercaptan were also determined for the a, p, and y hydrogen lines and the D line ; the principal results are given in the following table. J. W. Polymeric Thiocarbonyl Chloride. From pz. 8-85 7-45 7-63 ---- Substance. 9 -0" { ;: :; 11 '0 s:cc12 * . . . . . . . s:cc1~s*cc1~ . . SCl.CC1,. . . . . . 4.0 -20 76 -54 '76 -70 58 *93 23 -37 34 -19 The measurements for the polymeric tbiocarbonyl chloride were made on benzene solutions containing 16.139 and 15.549 per cent.respectively. It iu noteworthy that the atomic refractions of sulphur16 ABSTRAUTS OF OKFJMICAL PAPERS. deduced from these observations are considerably smaller than those observed by Nasini and Costa with similar compounds. W. J. P. Magnesium Nitride. By A. SMITS (Rec. Trav. C ~ ~ W L , 12, 198- 202) .-Magnesium nitride is prepared by heating magnesium powder It is a yellow substance, easily powdered, and must be kept in settled tcbes, as it is rapidly acted on by the moisture of the air. Although immediately decomposed by water. it is not acted on by glycerol or by oxalic acid dissolved i l l absolute alcohol. Nitrate of silver in alcoholic solution is reduced. A quantitive synthesis establishes the composition Mg3N,, a result confirmed by analyses.W. T. Lead Tetrachloride. By H. FRIEDRICH (Monatsh., 14,505-520 ; compare Abstr., 1890, 699 ; 1893, ii, 415 ; also Ciassen and Zahorbki, ibid., 1893, ii, 464) .--The author confirms the forniula PbC14,2NH4C 1 for the double chloride of lead and ammonium, to which Classen and Zaharski (Zoc. cit.) gave the formula 2PbC1,,5NH4CI, and is of th opinion that the compound analysed by those investigators contained flee ammonium chloride. The behaviour of the double salt 011 adding it to well-cooled sulphuric acid, whereby lead tetrachloride separated as an oily substance, was so remarkable that the author investigated the behaviour of ammonium stannichloride towards sulphuric acid, an? obtained a similar result, tin tetracliloride being formed.The tetrachlorides of lead and tin therefore closely resemble each other in regard to their stability in presence of sulphuric acid, and tin and germanium tetrachlorides may even be distilled from the concentrated acid without decomposition. On the other hand, the higher chlorides of iron and of antimony are readily decomposed by the acid with evolution of hydrogen chloride. Attempts to isolate lead tetrabromide or its double salt with an alkaline bromide have proved unsuccessful. G. T. DL ' i n a current of dry ammonia. Basic Copper Selenate and Basic Cobalt Selenate. By BOGDAN (Bdl. SOC. Chim., [3], 9, 584--586).-Basic copper selenate, %3e03,SCu0,4Hz0, or Cu(O*Se0z~OCu*OH)2 + 3Hz0, is obtained by heating a 10 per cent. solution of normal copper selenato in sealed tubes at 240-250" for several hours.It forms minute, transparent, emerald-green, prismatic crystals, insoluble in water but easily soluble in acids. When heated at about 250°, the salt loses water and decomposes with liberation of selenium. The fact that the salt does not lose water at 210" is not regarded by the author as evidence that the water is not present in the form of water of hydration. Basic cobalt selenate, 3Se03,4Co0,H20; or 0 H*Co0*Se02*0~Co0*SeO~*O*Co0 Se02*OCo-0 H, is obtained in a similar manner, and forms small, red, acicular crystals strictly analogous to the copper compound in general pro- perties. C. H. B.4 0 F i2 ; P. P. HJ drogen com- pounds. CdCl2,HC1,3frH,O SnC1,,HC1,3H20 Lithium com- pounds. MnC12,LiC1,3H20 FeC12,LiC1,3H20 NiCl,,LiC1,3 H20 CoC12,LiC1,3H20 CuC12,LiC1,2$H20 CdC12,LiC1,3frH20 SnCl4,LiC1,4H20 Ammonium compounds. MnCl2,NH4C1,ZH20 I NiC12,NH4C1,6H20 CoCl,,NIf,Cl,GH20 CuCl2,NH4C1 CdC12,NH4Cl,&H20 - MnC12,2NH4CI,H20 FeC1,,2NH4C1 Sodium corn.pounds. Potassium com- pounds. - FeC12,2KC1. - CuC12,2KCl,ZH20. c CuC12,KCl. CdCl,,KCi,+H20. SnC14,2KC1. Seo next page.18 ABSTRACTS OF OHEMIOAL PAPERS. New Double Chlorides. By A. CHASSEVANT (Ann. Chim. Phys., [6], 30, 5-56 ; compare Abstr., 1892, 118 and 1275).-The author has prepared and analysed most of the double salts the formuh of which appear in the table (preceding page); some of these are new, whilst others have already been described by himself and others. The arrangement renders clear the relations and differences which exist betmeen the salts.A. R. L. Decomposition of Alkali Stannates under the influence of Carbonic Anhydride and of Alkali Carbonates. By A. DITTE (Ann. Chim. Phys., [6], 30, 282-285).-Austen has"shown (Cl'zenz. News, 46, 286) that stannic oxide may be readilyprepared by passing a current of carbonic anhydride'into a solution of an alkali stannate containing an excess of alkali. When some bubbles of carbonic anhydride are allowed to fall on the surface of a, dilute solution of an alkali stannate, a cloudy separa- tion of gelatinous stannic oxide rises to the surface, and, as it in- creases in amount, the carbonic anhydride ceases to be absorbed. When, however, the carbonic anhydride is introduced rery slowly in contact with crystals of stannate, a dense monhydrated stannic oxide is formed, which seems to be amorphous. If carbonic anhydride is passed into a mixture of stannate and carbonate, stannic oxide falls to the bottom of t>e liquid. Alkali carbonate free from the acid salt does not give rise to the production of stannic oxide wben added to a stannate; stannic oxide is formed in amount proportional to the quantity of acid salt present. Preparation of Potassium Metantimonate. By DUYK (Chem. Centr., 1893, ii, 254; from Bull. Xoc. roy. Pharm. Bruxelles, 37, 109).-The method depends on eliminating the sulphur from the sulphantimonate by means of copper oxide. Black antimony sulphide (100 grams) , potassium carbonate (150 grams), slaked lime (100 grams), and sulphur (20 grams) are shaken with 12 litres of water, and after remaining eight days the mixture is filtered. The filtrate, which contains potassium sulphantimonate, is boiled with copper oxide (120 grams) and filtered. The filtrate is diluted with water and treated with carbonic anhydride, when potassium metantimonate is precipitated. E. C. R. A. R. L.