View Article Online / Journal Homepage / Table of Contents for this issue INORC ANIC CHEMISTRY. ii. 107 Inorganic C hernist ry. The Hydrides of the Metalloids. R. DE FORCRAND(J.Chim. Published on 01 January 1918. Downloaded 28/10/2014 04:37:21. phys., 1917, 15, 517-540).-An elaboration of work already pub- lished (compare A., 1905, ii, 696) and a discussion of Berthoud’s work on this subject (compare A., 1917, ii, 237). W. G. Hydrogen Peroxide as a Reducing Agent. M. KLEIKSTUCK (Rer., 1918, 51, lO&-lll).-SiIver chloride, suspended in potassium hydroxide solution, is quickly reduced by hydrogen peroxide accord- ing to the equation 2AgC1+ H,O, + 2KOH = 2Ag + 0, + 2KCI + H,O. Carbonyl chloride and phenyl carbonate also react with alkaline hydrogen peroxide, and so does a saturated solution of potassium hydrogen carbonate if kept at looo in a pressure bottle. The dis- tillate obtained by passing steam through the products reduces ammoniacal silver oxide, and is therefore said to contain form- aldehyde. The author sees in these reactions a new interpretation of the assimilation of carbon dioxide by plants, thus : H,CO, + H,O, -- CB,O + H,O + 30. [See also T)2TJ., April.] J. C. W. Variations of the Density of Air and the Loomis-Morley Law. PH.A. GUYE(J. Chim. phys., l917,15,561--566).--A study of the results obtained by various workers for the weight of a normal litre of air, in which it is shown that the results, taken its View Article Online ii. 108 ABSTRACTS OF CHEMICAL PAPERS. a whole, verify the qualitative experimental relation, stated by Loomis and Morley, between the density of the air and the baro- metric pressure. The most probable explanation of such varia- tions in density is based on the presence in the air of varying quantities of dust, invisible under the ultramicroscope. The mean of the most modern determinations gives the value 1.2928 grams as the weight of a normal litre of air. w. G. Portable Hydrogen Sulphide Generator. W. F,PITOUTE MUNN(J. Id. Eng. Chem., 1918, 10, 130--131).-A wide glass tube has two bulbs formed at its lower end, the bottom bulb being provided with a draw-off tap. A perforated lead plate is fitted at the constriction between the bulbs (a piece of glass tubing in the lower bulb acts as a support for the plate) and ferrous sulphide is filled into the UP er bulb. The acid reservoir consists of a large bulb, the stem o f which passes through a cork closing the top of the wide glass tube and extends to the bottom of the lower bulb. A tapped exit tube for the gas is placed near the top of the wide] tube, and this exit tube is fitted with a small washing tube. w. P. s. Automatic Hydrogen Sulphide Stopcock. CARLH. CLASSEN (J. Ind. Etzg. Chem., 1918, 10, 131--132).-To the delivery tube of the hydrogen sulphide apparatus is attached a length of rubber tubing in which is inserted a glass '' pearl " made from glass tubing having a diameter slightly larger than that of the rubber tubing. When the rubber tubing over the " pearl" is compressed between the finger and thumb, a channel for the flow of the gas is formed between the glass and the rubber. w. P. s. Chlor o- and B rorn o-aminosulphonic Acids. W ILH ELM Published on 01 January 1918. Downloaded 28/10/2014 04:37:21. TRAUBEand E. VON DRATHEN(Ber., 1918, 51, lll--115).-Solu- tions of potassium aminosulphonate and hypochlorous acid in equi- valent proportions react in the cold to form potassium chloroamino- stclphonate, NHCl*SO,K, which may bel isolated by evaporating the mixture to a small bulk, in a high vacuuni, at as low a tempera- ture as possible and precipitating with alcohol. The salt forms limpid, hygroscopic crystals, and is comparatively stable. When warmed with mineral acids, hydrolysis takes place according to the equation NHCl*SO,H + H,O = NH,CZ + H,SO,. The corre- sponding barium salt is not so stable, but potnssiicm bromoamino- sulphoncxte is very similar. Similar salts may be prepared by the interaction of free amino- sulphonic acid and metallic hypochlorites. Alkylaminosulphonates apparently give very unstable products, for evolution of gas is noticed as soon as hypochlorous acid is added. There are indications that a double amount of hypochlorous acid produces less stable dichloroaminosulphunates. J. C. W. Rate of Hydrolysis and Electrical Conductivity of Hypo- phosphoric Acid Solutions. R. G. VANNAVE and WILRERTJ' HVFF('4 mer. ,7. Sci., 1918, [iv], 45, 103--118).--The idometric View Article Online INORGANIC CHEMISTRY. ii. 109 method for the estimation of phosphorous acid in presence of hypo- phosphoric acid (this vol., ii, 128) has enabled the authors to in- vestigate the rate of hydrolysis of the latter acid. The data obt,ained at' 25O and 600 show that' in dilute solutdons containing hydrochloric acid as catalyst the hydrolysis proceeds in accordance with the equation for a unimolecular change. The velocity co- efficient increases much more rapidly than the hydrogen ion con- centration. The temperature coefficient for loo is 2.7. The fact that the hydrolysis follows a unimolecular law is in favour of the formula H4P90, rather than H,PO, for hypophosphoric acid, for the production of phosphorous and phosphoric acids would require the interaction of two molecules of acid if it had the simpler formula. For the conductivity measurements, pure solutions of the acid were prepared from lead and copper hypophosphate by the action of hydrogen sulphide at low temperatures. The metallic sulphides were filtered off and the excess of hydrogen sulphide removed by a current of air. The conductivity of the solutions after complete hydrolysis was also determined. The molecular conductivity at 25O referred to the formula H4P,0, increases from A = 384.7 at' E = 32 to A = 629-3 at 'u = 1024. After hydrolysis, the conductdvity of the stronger solutions is diminished, whilst that of the more dilute solutions is increased. Attention is directed to the resemblqnce between thel properties of hypophosphoric acid and pyrophosphoric acid. This resemblance is found in the conductivity of the solutions, in the behaviour towards indicators, and in their solubility relations, and may be adduced in support' of the formula H,P,O, for hypophosphoric acid. R.M. D. Preparation Amorphous Boron, WILHELMKROLL (Zeitsch. Published on 01 January 1918. Downloaded 28/10/2014 04:37:21. of nnorg. Chem., 1918, 102, 1-33).-The paper gives t8heresults of numerous experiments on the reduction of boron compounds. Aluminium is unsuitable. Sodium yields mixtures of the lower oxides of boron mixed with boride. Calcium produces only borides. Magnesium may be used for the reduction of boric acid, but the product contains more than 3% Mg in the form of in- soluble boride. The halogen compounds of boron can be reduced by potassium, sodium, magnesium, and aluminium; in each case, borides of the metal are formed as well as free boron. The purest boron is obtained by the reduction of boron chloride with hydrogen in the high tension electric arc. Red phosphorus does not reduce boric acid. When boric acid is heated with magnesium nitride, a boron n,itride, probably B,N, is produced. Boron nitride, BN, can be conveniently prepared from boric acid and calcium cyanamide. When boron chloride is passed over red phosphorus in the presence of oxygen, a yhocphntP, 5?B,O,P,O,, is formed. Other phosphates appear to exist. The original contains details as to analytical processes regarding compounds of boron. [See, further, Izd., 1484.1 R. V. S. View Article Online ii. 110 ABSTRACTS OF CHEMICAL PAPERS. Nomenclature of Silicon Compounds. ALFREDSrocK (h’er., 1917, 50, 1769-1771. Compare A., 1917, ii, 204).-The author again emphasises the fact that very little chemical similarity exists between silicon and carbon compounds of the same structure, and proposes to abandon the nomenclature of carbon chemistry as far as possible. For example, the radicle -SiO*OH in no way resembles a carboxyl group, and therefore the term “hydroxyoxo” is sug- gested in such a case. J. C. TY. Silicon Hydrides. 11. Bromination of Monosilane, SiH4. SiH,Br and SiH,Br,. ALFREDSTOCK and CARL SOJIIESKI(Ber., 1917, 50, 1739-1754. Compare A., 1916, ii, 319). -The experiments, fully described in this paper, had for their object the bromination of pure silane under conditions favourable to the production of the lower bromides. Under ordinary condi- tions, the reaction betwemen bromine and silane is very violent, but if an excess of the gas is led into a large vessel on the walls of which solid bromine is deposited, and the temperature is main- tained at about - 80° to - 70°, the mono- and di-substitution pro- ducts can be obtained comparatively free from SiHBr, and SiBr,. The apparatus employed is very elaborate (see A., 1917, ii, 442) and the manipulation is a matter of considerable difficulty. For details of the preparations and final fractionations, the original should be consulted. Bronzomonosilane, SiH3Br, is a colourless gas with a pungent odour, at the same time reminiscent of monosilane. It has m. p. -94O, b. p. +1-9O/760 mm., DO 1.533, and molecular latent heat of vaporisation 5.83 Cal. It may be preserved over mercury for some time, but it detonates on exposure to the air, giving silicic acid and brown silicon. It reacts with cold water according to Published on 01 January 1918. Downloaded 28/10/2014 04:37:21. the equation 2SiH,Br + H,O = 2HBr + (SiH,),O (see following abstract), whilst’ it may be aiialysed by measuring the volume of hydrogen produced under treatment, with 30% sodium hydroxide, according to the equation SiH,Br + 3NaOH = 3H2 + NaBr+ Na,SiO,.