Ills ABSTRACTS OF CHEMICAL PAPERS.I n o r g a n i c Chemistry,Combustible Organic Matter in the Air. By A. MUNTZ andE. AUBJN (Compt. rend., 99, 871--874).-The amount of combustibleorganic matter in the air was determined by two methods. In thefirst, a known volume of air, carehlly filtered from suspended matterand purified from carbonic anhydride, was passed over heated cupricoxide, and the volume of carbonic anhydride produced by the com-bustion of the organic matter was measured. In the second, theamount of carbonic auhydride in 1000-1500 litres of air was deter-mined by the method previously described (Le., by passing the airthrough a tube containing potash pumice), and an equal volume ofair taken a t the same place and a t the same time was passed overheated cupric oxide, and the amount of carbonic anhydride formedwas estimdted.The difference between this amount and that alreadyexisting in the air is the aruonrit produced bay the combustion of theorganic matter, Both methods gave identical results.At Paris, the amount of carbonic anhydride formed by the combus-tion of the atmospheric organic matter varies between 3 and 10 vols.per 1,000,000 vols. of air. At Vincennes the volume varies from2-0 to 4.7 per million, the mean result for October, November, andDecember, 1882, being 3.3 vols. It would seem, therefore, that theamount of organic matter in the air is represented by a volume ofcarbonic anhydride equal to one-hundredth part of the volume ofcarbonic anhydride existing as such in the atmosphere.If it is assumed that all the combustible carbon is present in theair as methane, the volume of the hydrogen contained in the latterwill be 16 per million of air, or, in Paris, 33 vols.per million, a num-ber which agrees well with the lower values foutld by BoussingaultINORGANIC CHEMISTRY. 119When electric discharges are passed through the air, the com-bustible organic matter is more or leas completely burnt, and there islittle doubt that the electric discharges which take place in the loaerregions of the atmosphere destroy a considerable proportion of thecombustible organic matter which the latter contains. C. H. B.Reactions with Carbon and some of its Compounds. ByG. GORE (Chem. News, 50, 124--126).-When white or red phos-phorus, or powdered arsenic or antimony or sodium, are added toiused poiassium cyanide ; or when aluminium or sodium phosphide,or‘ a mixture of sodium phosphide with zinc, is added to fused potassiumand sodium carbonates ; or when sodium carbonate is decomposed ata low red heat by phosphorus vapour ; or wlien a mixture of red phos-phorus and ammonium carbonate is dropped into a red-hot porcelaincrucible, a black substance separates, which i n some cases is found tobe carbon.Carbon is also obtained when coal-gas is passed over red-liot finely-powdered ferric oxide, or over just fused argentic fluorideor chloride, or over chloride of lead or copper. Arsenic and anti-mony do not visibly decompose fused sodium and potassium carbo-nates ; neither is carbon set free when ammonium carbonate is addedto fused sodium; nor when cod-gas is passed over fused cadmiumchloride or silver iodide ; nor in several experiments wherein nume-rous hydrocarbons, in various solvents, were exposed to metals andmetallic couples.Several unsuccessful attempts a t deoxidising car-bonic anhydride are also described along with many experimeotswherein many substances alone and in contact were immersed invarious solutions of metallic salts contaiiiing carbon in combination,and in these solutions when exposed t o carboniferous yapours, but inall cases without any deposition of carbon. The chlorides of carbonproved equally useless as sources of carbon, even resisting the influeuceof potassium, which however fornied an alkaline salt with carbon t’etra-chloI ide ; potassium or sodium, dissolved in anhydrous liquid ammoniaat 60” F., behaved in a similar manner with carbon bromide and sul-phide, and with anhydrous sodium carbonate or formate, or ammoniumoxalate. On passing dry ammonia gas into liquid carbon dichloridecontaining potassium, gas was evolved, and a red powder formed ; withnaphtha instead of the chloride, the potassium only became red.Carbonis insoluble in anhydrous liquid cyanogen, sulyhuric chloride, phos-phorus trichloride, antimony pentachloride, anhydrous liquid hydro-fluoric and hydrochloric acids : chlorides of carbon and bisulphide ofcarbon were also found to be insoluble in the last two acids, but theyare soluble in liquid cyanogen.Many experiments with carbon bisul-phide are described ; for example, when silver and platilium in con-tact are immersed in it, after some time the silver blackens ; in thesame way lead and mercury yield a black powder soluble in nitric:acid. Thallium also blackens, but no action could be observed withtin, or magnesium and platinum, or with boron fluoride; tin tetra-chloride, thallium chloride, and cyanogen are dissolved by it, and itprecipitates mercuric chloride from its solution in ether. The solutionsof sulphur and phosphorus in carbon bisulphide give no reaction whenexposed in an atmosphere of carbonic anhydride; zinc remains brigli120 ABSTRACTS OF CHEMICAL PAPERS.in the sulphur solution and potassium and platinum in contact causeno free carbon to separate from i t ; aluminium and magnesiumbecome dull, but are not corroded by prolonged exposure in thephosphorus solution.When a solution of silver nitrate with a pieceof platinum partly immersed in it was exposed to carbon bisulphidevapour continuously for seven weeks, all the silver was precipitated ;magnesium, aluminium, or silver partly immersed in water exposed tothe same vapour, were unaltered ; when, however, the silver was incontact with plabinum, the liquid became dark and the silver abovei t blackened. A liquid which dissolved selenium was obtained bypassing the vapour of selenium over charcoal powder kept at a fullred heat. D. A. L.Polymorphism of Silicon Phosphate. Ry P. HAUTEFEUILTBand J. MARGOTTET (Compt.rend., 99, 789--792).-Hydmted silicadissolves readily when heated with orthophosphoric acid, and thesolution deposits crystallised silicon phosphate in forms varying withthe temperature at which the deposition takes place. When an in-timate mixture of phosphoric acid and hydrated silica is graduallyheated to 260°, about 5 per cent. of silica is dissolved, and a stiillarger proportion can be obtained in solution by gradually heating amixture of phosphoric acid with silicon chloride.When the solution of silica in phosphoric acid is allowed to coolbelow 260", it deposits crystals having the appearance of flatteneddiscs. Similar crystals are obtained when the solution is mixed withstrong sulphuric acid and heated for some time at a temperaturesomewhat above the boiling point of the latter. These crystals arehexagonal prisms, frequently macled in the same manner as lamellarhmmatite.They act strongly on polarised light, and are somewhatrapidly attacked by water, but do not alter in contact with alcohol.If the temperature of the solution of silica is gradually raised from260" to about 360", it deposits an abundance of very thin hexagonallamellm, which act feebly on polarised light and resemble tridyniite inappearance. They are, however, distinguished from the latter by thefact that they yield silver pbosphate when fused with silver nitrate.These Iamelle are not altered by alcohol, but are slowly attacked bywater with formation of phosphoric acid and sohxble silica.If the solution of silica is heated rapidly, it remains limpid up toabout 700", but between 700" and 800" it deposits regular octahedrawhich are almost always modified by cubical faces.This form ofsilicon phosphate has already been described (Abstr., 1883, 782).When phosphoric acid containing only a small proportion of silica,is rapidly heated to about 900-1000", the crystals obtained are mono-clinic prisms which act strongly on polarised light. A t a high tempe-rature, these prisms are more sfhble than the other forms. If phos-phoric acid saturated with silica is slowly heated to lOOO", a mixtureof all four forms is obtained; but if the temperature is maintainedthe lamella3 and octahedra are quickly attacked, whilst the prismscontinue to increase.They allhave the composition P20,,Si02.The hexagonal crystals are formedThe crystals were analysed by fusion with silver nitrateINOROANIC CHENISTRY. 121below 300°, the lamellae resembling tridymite at about 360", the regu-lar octahedra between 700" and 800°, and the monoclinic prismsbetween 800" and 1000". This polymorphism is not due to differentgroupings of the same crystalline elements, for the hexagonal crystalsare attacked by water, which has no action on the octahedra, orprisms.Other phosphates behave in a similar manner. C. H. B.Crystalline Phosphorous Anhydride. By J. M. CABELL (Chew.News, 50,209).-The mixture of oxides obtained by burning phosphoruswith a limited supply of air was placed at both ends of a long tube,the intervening space being empty ; carefully dried and purifiedhydrogen was then passed through the tube and the foremost portionof the oxides gently heated. At about 350' F.crystals were depositedin the empty portion of the tube, whilst the residue became semi-fused. The crysfals, apparently monoclinic, could not be measured ;when quickly transferred to litmns-paper they did not redden it forsome seconds. Their solution did not give phosphoric acid reactionswith either ammonium molybdate or magnesia mixture; but afterwarming with nitric acid both reactions were obtained. It is henceinferred-that these are crystals of phospltorous anhydride.D. A. L.Arsenic Trifluoride. By H. MOBSAN (Comnpt. rend., 99,874-876).-A rsenic trifluoride was obtained by heating calcium fluoride andarsenious oxide with sulphuric acid.It forms a colourless, verymobile liquid, which boils at 63" under a pressure of 752 mm., andfumes in the air ; sp. gr. = 2,734. It dissolves a certain quantity ofiodine, acquiring a purple-red colour, and combines with bromine atR gentle heat, forming a crystalline compound. When heated to dullredness in a glass vessel, i t yields silicon fluoride and arsenious oxide,but no metallic arsenic is liberated: 4AsF3 + 3sio2 = 2As20, +3SiF4. When the arsenious fluoride is electrolysed in a platinumvessel by means of 25 Bnnsen elements arranged in series, metallicarsenic is deposited, and a gas is given off at the positive electrodewhich, although made of platinum, is superficially attacked.C. H.B.Specific Gravity of Sulphuric Acid. By D. MENDELLEFF (Bey.,17, 2536-2541).--8 reply to Lunge (Abstr., 1884, 1256), in whichthe author upholds the correctness of his density 1.8371 at 1 5 O __ asagainst that of 1.8384 found by Lunge.4 OL. T. T.Octosulphates. By R. WEBER (Bey., 17, 2497--2503).-By heat-ing carefully dried sulphates with excess of sulphuric anhydride, theauthor has obtained a series of well characterised salts of the generalformula M'20,8S03. The product while still hot consists of twolayers, the upper one being unchanged anhydride. The salt solidifiesas it cools, and the still liquid anhydride may be poured off, andthe last traces caref ullg distilled off at about 60"122 ABS L'RACTS OF CRE'MICAL PAPERS.The ptassium salt, K20,8S03, melts in the presence of excess ofsulphuric anhydride a t 80" : when isolated, it is slowly decomposed a tthe boiling point, of the anhydride, yielding first K20,2S03, and finallyK,SO,.Ruhidiuw andc ~ s i z i m behave exactly like potassium, but no corresponding sodiumor lithium compound could be obtained. The nmmoniurn salt,(NH4),0,8S0,, is formed even more easily than the potassium salt.Of the heavy metds, thaZZium alone seems capable of forming anoctosulphnte. Its crystals seem to be isomorphous with those of thepot,assium compound, and, like the latter, i t yields a disulphate,Tl2O,2SO,, when heated. 8iltwr yields a disulpkate, AmO,BSO,, underthis treatment, but no higher sulphate could be obtained. Theanalogy of thallium to potassium, and the dissimilarity therefrom ofsodium and lithium, are noticeable.It crystnllises from the fused mass in prisms.L.T. T.Action of Water on Double Salts. Rg F. M. RAOULT (Compt.rend., 99, 914-916).--.The author has dekermined the molecularreduction of the freezing point produced by various double saltscontaining more than one molecule of the acid radicle, with the resultsgiven in the following table, where A is the observed molecularreduction and S the sum of the molecular rednctions producedseparately by each of the simple salts of which the double salt iscomposed : --K2SOa,MgS04 . . 57.7 58.2K,SO,,Zn<O, .. 58.1 57.2K,SOo,FeSOI . . 56.5 58.0A. S.RZSO1,CuSOI .. 58.3 57.0K2SO~,A1,3SO~ . 82.4 83.4K,S04,Fe23S04.85.0 82.1K2SOa,Cr23S04 . 83.2 84.4A.2KCl,MqCl, . . 117.22KCI,CuC11, .. 116.82AmCl,H~:Cl,. 68.42NaC1,PtC14 . . 54.22KI,HgT, . . . . 50.82KCy,HgCy?. . 57.3KCy,AgCy .. 31.1It is evident that many double salts, espec:ially the alums and thedouble sulphates and double chlorides of the magnesium group ofmetals, produce a molecular reduction of the freezing point practicallyidentical with the sum of the molecular reductions produced separatelyby each constituent salt. In other words, thev behave in sohitioii asif the constituent salts were merely mixed and not in actual combilia-tion, a result which agrees perfectly with therrnochemical observa-tions. In the case of the last five salts in the table, however, thisdoes not hold good, and i t follows that these double salts ar'e notcompletely decomposed by wa! er, a result agreeing with therrno-chemical observatAms, which show that the formation of each of thelast three is accompanied by the development of a considerableamount of heat.From these results, i t follows that a comparison of the observdmolecular reduction of the freezirig point produced by a given doublesalt wilh the sum of the partid reductions produced by each con-stituent, will show whether the double salt is or is not compleit.lydecomposed when it is dissolved in water.If it is assumed that the molecular reduction produced by a givcISORGANIC: CHEMISTRY.123double salt is equal to the mean molecular reduction of the potassinrnsalts containing the same number of atoms in the molecule (a sup-position which is supported by the known beh,iviour of silver potas-sium cyanide), it is possible to calculate the amonnt of decompositionwhich each salt experiences when dissolved.Some of the numbersthus obtained are given in the following table. They represent thatfraction of the molecule of the double salt which is decomposed bywater :-KCy +2KCy +2KI +2AmCl+2XaCl +2KC1 +KYSO, +K&Oi +AgCy + water (2 litres) . . . . . . . .HpCx. + mater (10 litres). . . . . . . .HgI, + water (4 litres) . . . . . . . .HgCI, + u-ater (10 litres). . . . . . . .PIC1, + water (4 litres) . . . . . . . .MgCl, and analogous chlorides . . . .MgSO4 ,, sulphates . . . .A123SOd .... 1 ) ?,0.000.380.380.590.261.001.001.00C. H.B.Magnesium Suboxide. By G. GORE (Chem. Nezus, 50, 157).--Beet2 (Phil. JIag., 1866, 269) observed, when magnesium elec-trodes were used for the electrolysis of a solution of sodium chloride,that a black substance was formed on the positive pole, and from thefact that it evolved hpdrogen in contact with certain aqueous solutions,he concluded that i t was magnesium suboxide.The author has observed a similar phenomenon under the followingconditions :-When magnesium alone is partly immersed in water and exposedto coal-gas, carbonic anhydride, vapour of CCI, or CpC14, or when it i simmersed in a mixture of absolute alcohol with glacial acet,ic acid ;the deposition is slight with magnesium in liquefied glacial acetic acidalone, or in a solution of toluene or formic acid in absolute alcohol, orin a mixtiire of glacial acetic, with either sulphuric acid or vegetablenaphtha.On the. other hand, the deposition is more rapid in all thesecases when the magnesium is in contact with either platinum, gold,silver, or iron, and most rapid with palladium. Magnesium andplatinum in contact, produce it' when they are immersed in a solution ofeither creosote, toluene, or xylene in vegetable naphtha, or in a solutioncontaining 1.25 mm. of hydrochloric acid per ounce of water. Theblack deposit is also formed when magnesium alone is immersed insolutions of the following salts containing 5 grains of salt per ouilce ofwater :-potassium, sodium, ammonium, lithium, barium, stront;um,calcium, and magnesium chlorides, bromides of the first thyee, andpotassium iodide, the sodium chloride solution giving the largestamount.I n all cases it appeared within the first few daJs, sub-sequently disappearing with the simultaneous formation of whitemagnesium hydroxide. From all these facts, i t is evident that theblack substance comes from the magnesiiim. It turns white whenheated t= a temperature below redness. I t is soluble in dilute nitricacid, yielding a green solution owing tlo reduetion ; hjdrochluric aridsulphuric acids dissolve it with effervescelice. Its hydrochloric acaidsolution contains magnesium chloride only. These results confirn124 ABSTRACTS OF CHEMICAL PAPERS.Beetz's conclusion, namely, that this substance is magnesium szhb-oxide.D. A. L.Copper Peroxide. By G. R R ~ S S (Ber., 17, 259:3-2597).-Theexperiments by Thknard seemed to indicate the formation of a copperperoxide by the agitation of cupric oxide with a dilute solution ofhydrogen peroxide. In this paper, a description is given of a repeti-tion of this work, and it is shown that if very finely divided cupricoxide is agitated for several days with hydrogen peroxide there isgradually formed an olive-green precipitate of composition C uOz,H,O.It is decomposed at a temperature of 6" when moist, but is far morestable when dry. The formation of this compound points to thetetratomicity of copper. From other experiments, it would appear thatan oxide can be obtained intermediate in composition between cupricoxide and peroxide, formed by heating cupric oxide with caustic potash,or potassium or sodium chlorides.Decomposition of Cupric Oxide by Heat.By E. J. MAUMEN~(Cornpt. rend., 99, 757-759).-A criticism on the papers by Debrayand Joannis (this vol., pp. 21 and 22).V. H. V.C. H. B.Action of Hydrogen Sulphide on Metallic Silver. By J. M.CABELL (Chem. News, 50, 208--209).-The author has made fourexperiments in which very carefully cleaned pure silver was exposedunder certain varying conditions to a current of pure hydrogen sul-phide, which was first carefully dried. The results tend to show that,in absence of water, hydrogen sulphide does not act on silver at theordinary temperature. D. A. L.Silver Hydroxide. By J.D. BRUCE (Chem. News, 50, 208).-When dilute solutions of silver nitrate and potassium hydroxide, in90 per cent. alcohol, are mixed at the ordinary temperature, in quan-tities containing equivalent amounts of the two substances (AgNO,and KHO), the usual granular brown precipitate of silver oxide isformed, When, however, the mixing is effected at very low tempera-tures, the precipitate which forms is flocculent, and has less and lesscolour as the temperature is lowered, until at about -50" F. the precipi-tate is almost white. This white precipitate soon becomes coloured,and a t -440" F. is already pale brown. The white precipitate ispresumably silver hydroxide, and is but slightly soluble in water.Hydrated Aluminium Sulphate.By P. M. DELACHARLONNY(Compt. rend., 99,800--801).-When a moist mass of crystals of normalaluminium sulphate, Alz3S0,,l6H,O, is cooled to 6--8", crystals of anew hydrate, A1,3SO4,27H,O, are gradually formed. These crystalsare hexagonal prisms modified by faces of the rhombohedron in the samemanner as crystals of dioptase. They are formed only below 9*5", andwhen exposed to the air a t ordinary temperatures they give off waterand are reconverted into t'he hydrate Al23SO4,16H2O. The samechange is brought about by mechanical disturbance, such .as crushiiigthe crystals with a pestle. The crystals can, however, be preserved inn. A. LNINERALOQICXL CHXMISTRY. 125closed flasks without undergoing any alteration. The forniation of thishydrate from the ordinary hydrate is much facilitated by mixing thelatter with some ready-formed crystals of the former.Reaction between Ferric Oxide and certain Sulphates atHigh Temperatures. By SCHEURER-KESTNER (Compt. rend., 99,876--877).-When a mixture of t w o parts of calcium sulphate and onepart' ferric oxide is heated to bright redness, it fuses, the whole of thesulphur is expelled, and a residue of ferric and calciuni oxides is left,soluble in dilute acids. Even acetic acid gradually removes thecalcium in the cold. During the decomposition, sulphuric anhydrideis first evolved, and afterwards, as the temperature rises, sulphurousanhydride and oxygen. Probably the mixture fuses and calciumoxide and ferric sulphats are Eormed, the latter being afterwardsdecomposed. By adding a fl~ix, such a9 calcium chloride or fluoride,decomposition takes place at a lower temperature, but the crucible ismuch corroded.Lead sulphate is decomposed in the same way a t a somewhat, lowertemperature, The residue dissolves in dilute nitric acid withoutevolution of nitrogen oxides, and acetic acid gradually dissolves outthe lead in the cold. Magnesium sulpllate behaves in a similarmanner, but does not fuse, and only sulphurous anhydride and oxygenare given off without any sulphuric anhydride.C. H. B.C. H. B