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Inorganic Chemistry.

Combustion of Weighed Amounts of Hydrogen; Atomic Weight of Oxygen. By E. H. KEISER (Ber., 20, 2323-2325).— Palladium was weighed with and without occluded hydrogen, it was then heated, and the hydrogen thus expelled passed over heated copper oxide. The water which was formed was also weighed. 1.5935 grams of hydrogen (from three experiments) gave 14.23972 grams of water. The atomic weight of oxygen calculated from these numbers is 15.872. The number obtained from Stas's figures is 15.84 (Ostwald, Allgem. Chem., 1, 43). The author intends repeating the experiments with large amounts of palladium. N. H. M.

Composition of Generator-gas and Water-gas. By F. FISCHER (Ber., 20, 2551-2553).-The following results are given :

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The analyses were made in a special apparatus, which, however, presents no very novel features. W. P. W.

Tellurium Dichloride. By A. MICHAELIS (Ber., 20, 2488-2492). -Tellurium dichloride melts at about 175°, and boils constantly at 324°. The vapour-density was determined in an atmosphere of nitrogen at the temperature of boiling sulphur, and the following values were obtained: 6·9, 6·6, 7·0, compared with 6-89, the value calculated. for TeCl2; moreover, there is no indication that the vapour has a greater density at lower temperatures. The vapour of the dichloride is dull red in colour, and gives a characteristic absorption-spectrum (Gernez, this Journal, 1872, 665), in which the bands, whose positions on an arbitrary scale are given, lie between Fraunhofer's lines b and C. When heated in an open tube, the vapour of the dichloride becomes brighter in colour, and finally assumes a pure yellow. This change in colour is accompanied by the disappearance of the absorption-bands, and is due to the oxidation of the dichloride when heated in air, since the compound when heated in a current of oxygen is converted into a mixture of tellurium tetrachloride and tellurium dioxide, together

with the oxychloride TeOCl2, if the heating is continued for some time. The vapour of the tetrachloride is yellow, and gives no absorptionspectrum, a fact which confirms the point brought out in the vapourdensity determinations (this vol., p. 770), that the compound is stable, and does not decompose into chlorine and the dichloride when vaporised. W. P. W.

Working-up of Stassfurt Potash Liquors containing a Large Excess of Sodium Chloride. By H. FISCHER (J. pr. Chem. [2], 36, 222-224).-Boiling water dissolves much more potassium chloride and sulphate but hardly any more sodium chloride than cold water. Potassium sulphate and potassium magnesium sulphate are less soluble in cold water than potassium and sodium chlorides; and finally the presence of magnesium chloride reduces the solubility of all the above salts except potassium chloride.

Advantage is taken of these relationships to isolate potassium chloride from saline solutions containing but little of this substance. End-liquors (rich in magnesium chloride) are added until the solution contains about a quarter as much magnesium chloride as sodium chloride, and the whole is then concentrated. Sodium chloride separates out first, and then potassium sulphate and potassium magnesium sulphate, potassium chloride remaining dissolved. L. T. T.

By P.

Crystalline Form of Potassium Aurobromide. SCHOTTLÄNDER (Annalen, 240, 346–348).—Potassium aurobromide crystallises in the monoclinic system.

a b c = 0.79688: 1: 0.3610 β = 85° 34' 2".

W. C. W.

Analysis and Properties of Phosphorised Silver. By H. N. WARREN (Chem. News, 56, 113).-When phosphorus is added to molten silver, the metal on cooling ejects the phosphorus; it however retains sufficient to give the silver a yellow colour, and to prevent it from spitting. The amount retained seldom exceeds 0.002 per cent. of phosphorus, but this is exceedingly difficult to expel by cupellation. D. A. L.

v. d. Pfordten's Silver Suboxide. By C. FRIEDHEIM (Ber., 20, 2554 2557). The composition of the so-called silver suboxide prepared by v. d. Pfordten (this vol., p. 699) was determined by titration with permanganate, which is stated in the paper to be without action on metallic silver. The author, however, finds that when very finely divided ("molecular ") silver suspended in water acidified with dilute sulphuric acid (1:5) is titrated with permanganate, the colour disappears as in oxalic acid titrations, slowly at first, then more quickly, and silver goes quantitatively into solution. Experiments made simultaneously with similar quantities of materials show that solution of the metal does not occur in the mixture of silver and sulphuric acid, and that the permanganate is not decolorised when added to the sulphuric acid. Moreover, compact silver is also attacked by permanganate acidified with dilute sulphuric acid; thus in an experiment with 1.5 grams of silver foil, 1 gram was dissolved when shaken for

two hours with the acidified permanganate, and brown flocks of what seems to be a compound of silver oxide with a higher oxidation product of manganese were simultaneously formed.

Following v. d. Pfordten's directions in every particular, a substance was prepared which, to judge from the published description, was identical with the so-called silver suboxide. On titration with permanganate, however, the ratio Ag: 0 = 2: 1 was obtained, and further, the volume of the gas not absorbed by aqueous soda which was given off when the substance, after careful drying in an atmosphere of carbonic anhydride, was slowly heated to bright redness was so small that the preparation must have been silver in an almost pure state; moreover, on dissolving the ignited silver in an acid, a residue of carbon was left. These facts lead the author to the conclusion that v. d. Pfordten's silver suboxide is nothing more than finely divided silver rendered impure by the presence of more or less silver oxide or organic substances. W. P. W.

Basic Zinc and Cadmium Nitrates. By H. L. WELLS (Amer. Chem. J., 9, 304-308).-By treating zinc or cadmium nitrate in hot solution with the oxides, and allowing it to cool, crystals of the basic salts, 2ZnO,NO,,3H,O or 2CdO,N2O,,3H,O, separate, the first in thin scales, the second in needles. Both are decomposed by washing with water, and must therefore be purified by washing with absolute alcohol. The basic salts previously described have been prepared by heating the normal nitrates, or by treating them with ammonia; none of these were washed with alcohol.. H. B.

Basic Lead Nitrates. By A. J. WAKEMAN and H. L. WELLS (Amer. Chem. J., 9, 299-303).-Besides the basic lead nitrate NO, Pb OH, the following salts have been described :

6Pb0,2N2O5,3H2O, Berzelius and Meissner; 6PbO,2N2O,H2O, Meissner, Löwe, and Smolka; 6PbO,2N2O5,2H2O, Löwe;

6Pb0,2N2O5,6H2O,

Volge; 10Pb0,3N2O5,5H2O, Smolka and Morawski.

The first salt is prepared without difficulty, but the others prove to be incapable of recrystallisation, or to be mixtures, or to have been imperfectly analysed, the only other recrystallisable basic salt being 10Pb0,3N2O5,4H2O. This substance forms flat, tabular crystals of triclinic habit, with an extinction angle of 35°; it is less soluble than the diplumbic nitrate, and suffers no change by boiling with water or on recrystallisation. All the preparations were examined microscopically, and all mixtures rejected. H. B.

Relations of Mercury to other Metals. By A. C. COUSINS (Chem. News, 56, 113-114).-Attention is drawn to the following coincidences:-The atomic weight of mercury is the mean of the atomic weights of gold and thallium. Its sp. gr. in the liquid state is very nearly the mean of their atomic volumes. Its atomic volume is almost the theoretical sp. gr. of an alloy of equal weights of gold and thallium. D. A. L.

Gallium. By L. DE BOISBAUDRAN (Ann. Chim. Phys. [6], 11, 429 -430).-Gallium chloride twice evaporated to dryness and dried at 100° loses by volatilisation about 06 per cent. of gallium. The amount of volatilisation from a hydrochloric acid solution of gallium chloride heated gradually to redness in presence of sulphuric acid, cannot be recognised with 0.08 gram of the chloride. C. H. B.

Metallic Manganese. By T. T. P. B. WARREN (Chem. News, 56, 27).—The author found that a sample of manganese he examined was either non-magnetic or only very slightly magnetic. It contained a small quantity of petroleum, which probably affected its magnetic properties. D. A. L.

Compound of Manganese Sesquioxide with Cupric Oxide. By E. A. SCHNEIDER (Amer. Chem. J., 9, 269-274).-Although many compounds of sesquioxides and protoxides are known, none have been prepared in which manganese sesquioxide plays the part of an acid oxide, and only two have been prepared in which copper oxide plays the part of a basic oxide, namely the compounds CuÔ‚Fe̟2O, + 5H2O and CuO,Cr2O3, and none in which silver oxide or mercuric oxide act in a similar manner.

An ammoniacal cupric oxide solution is mixed with aqueous soda, and to the deep blue solution aqueous manganous chloride is added, best drop by drop, with constant stirring. If the copper oxide and manganic oxides are used in the molecular ratio 1:1 or 2 : 1, the whole of the copper is at once removed, but with the ratios 3 : 1 or 4: 1 or 5 1 a portion of the copper remains in solution. The black precipitate thrown down in each case seems to have the composition Mn2O3,3CuO, although when an excess of copper solution is not used the precipitate approximates more towards Mn2O3,2CuO. The oxida tion is effected by atmospheric air.

H. B.

Peculiar Formation in Nickel Regulus. By T. MOORE (Chem. News, 56, 3).—On allowing a molten nickel regulus to cool slowly, brilliant flakes separated out, of a symmetrical form, and very ductile and malleable. These flakes had the following composition:-(a.) Cu, 160; Ni, 70-30; Fe, 28:30. (b.) Cu, 0-25; Ni, 87-863; Fe, 11.865 per cent. Regulus (a) contained 13.5 per cent. Fe; (b), 15·6. By the exclusion of copper, flakes were obtained composed of 86:40 per cent. Ni with 13.72 Fe, the surrounding regulus containing Ni, 72.10; Fe, 2:32; S, 25.51; whilst the regulus cooled suddenly to prevent formation of flakes had per cent., Ni, 73·80; Fe, 4·27; S, 22:01. It is curious to note the formation of such an alloy, and especially a malleable alloy, in the presence of sulphur. Under favourable conditions, the regulus may contain 10 per cent. of this alloy.

D. A. L. Germanium. By C. WINKLER (J. pr. Chem. [2], 36, 177-209). -In the present communication, the author details the further progress of his researches (Abstr., 1886, 985) on germanium. The investigation of this element is rendered difficult, as the argyrodite vein in the Himmelsfurt Mine is exhausted, and the quantity of 4 d

VOL. LII.

argyrodite in hand is small; this mineral is mainly found as a thin coating over other silver ore, the percentage of germanium in some of the richest ores being only about 003 per cent. Slight variations in the mode of extracting the element from the ore from those previously given (loc. cit.) are described. The sparing solubility of potassium germaniofluoride may also be employed for this purpose. Powdered argyrodite is mixed with nitre and potassium carbonate, and the mixture introduced in small quantities into a red-hot Hessian crucible. On cooling, two layers are obtained, the lower of silver, the upper of alkali salts. The upper layer, containing all the germanium, is powdered, boiled in water, and the filtered solution treated with excess of sulphuric acid and evaporated to dryness. This acid residue is then dissolved in cold water, when almost all the germanium oxide is gradually deposited from the solution. The remaining germanium is precipitated by hydrogen sulphide, and the sulphide converted into oxide by treatment with nitric acid. The oxides are mixed, dissolved in aqueous hydrofluoric acid, and filtered if necessary; potassium fluoride is added, and the double fluoride separates out. This fluoride is then converted into soluble thio-salt by fusion with potassium carbonate and sulphur, or by digestion with ammonium sulphide, this is decomposed by sulphuric acid, and the germanium precipitated as sulphide with hydrogen sulphide. This sulphide, when mixed with a little sulphuric acid and gently heated, yields a mixture of sulphide and oxide, which is converted into oxide by roasting and treatment with nitric acid. The oxide may be reduced by hydrogen, but if at all in large quantity the following method is preferable :-The powdered oxide is mixed with about 15 to 20 per cent. of starch, and kneaded with a little boiling water into small balls, which are dried at a low heat. These are introduced into crucibles between layers of powdered charcoal, and the whole kept at a bright red heat for about an hour. In this way, a somewhat porous regulus of germanium is obtained, which may be fused with powdered borax glass, and so obtained as a brittle, metallic bead.

When germanium is gently heated in a current of hydrogen chloride, the metal becomes red-hot, hydrogen is evolved, and two liquids of almost identical specific gravity are formed. After some time these separate into two layers. The heavier is the colourless, thin liquid boiling at 72°, previously described (loc. cit.) as possibly germanious chloride. Analysis, however, showed it to be germanium chloroform, Ge HCl. It is very easily oxidised in contact with air, apparently yielding the oxychloride, and at a high temperature seems to break up according to the equation 2GeHCl, Ge + GeCl + 2HCl. A vapourdensity determination made by Victor Meyer's method at 178° gave 5-55, theory requiring 6.21. The second liquid is germanium oxychloride, GeOCl2 (?). It is a colourless, non-fuming, oily liquid, which adheres strongly to glass. It boils much above 100°, seemingly without decomposition, but has not yet been obtained quite pure. The author hopes to obtain germanious chloride by heating germanious sulphide in an atmosphere of hydrochloric acid. Germanic chloride (loc. cit.) may be obtained by heating a mixture of germanic sulphide and mercuric chloride. It remains liquid at -100°. Germanic bromide,

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