Boron hydride has probably never been isolated in the pure condition; on heating boron trioxide with magnesium filings, a magnesium boride Mg 3 B 2 is obtained, and if this be decomposed with dilute hydrochloric acid a very evil-smelling gas, consisting of a mixture of hydrogen and boron hydride, is obtained.
In the same year Berzelius discovered selenium in a deposit from sulphuric acid chambers, his masterly investigation including a study of the hydride, oxides and other compounds.
Further, since methane may be regarded as formed b y the conjunction of a methyl group with a hydrogen atom, it may be named " methyl hydride "; similarly ethane is " ethyl hydride," propane, " propyl hydride," and so on.
P. 862), calcium is heated in a current of hydrogen, and nitrogen passed over the hydride so formed; this gives ammonia and calcium nitride, the latter of which gives up its nitrogen as ammonia and reforms the hydride when heated in a current of hydrogen.
When heated to 250° C. with red phosphorus and hydriodic acid it gives a hydride It is nitrated by nitric acid and sulphonated by sulphuric acid.
Columbium hydride, CbH, is obtained as a greyish metallic powder, when the double fluoride, CbF 5, 2 KF, is reduced with sodium.
Silicon hydride, SiH4, is obtained in an impure condition, as a spontaneously inflammable gas, by decomposing magnesium silicide with hydrochloric acid, or by the direct union of silicon and hydrogen in the electric arc. In the pure state it may be prepared by decomposing ethyl silicoformate in the presence of sodium (C. Friedel and A.
A second hydride of silicon, of composition Si 2 H 6, was prepared by H.
These are passed through a vessel surrounded by a freezing mixture and on fractionating the product the hydride distils over as a colourless liquid which boils at 52° C. It is also obtained by the decomposition of lithium silicide with concentrated hydrochloric acid.
For a possible hydride (S12H3)7, see J.
It is also obtained by the action of hydriodic acid on silicon nitrogen hydride suspended in carbon bisulphide, or by the action of a benzene solution of hydriodic acid on trianilino-silicon hydride (0.
Silicon nitrogen hydride, SiNH, is a white powder formed with silicon amide when ammonia gas (diluted with hydrogen) is brought into contact with the vapour of silicon chloroform at -10° C. Trianilino silicon hydride, SiH (NHC 6 H 5) 3, is obtained by the action of aniline on a benzene solution of silicon chloroform.
It decomposes water at ordinary temperature with evolution of hydrogen but without production of silicon hydride, whilst cold hydrochloric acid attacks it vigorously with evolution of hydrogen and spontaneously inflammable silicon hydride.
Siemens and Halske have proposed the addition of oxidizing agents such as free halogens, to prevent the formation of zinc hydride, to which they attribute the formation of zincsponge.
By passing chloroform vapour over the heated dioxide the tetradiand tri-chlorides are formed, together with the free metal and a gaseous hydride, TiH 4 (Renz, Ber., 1906, 39, p. 2 49).
Guntz and Roederer (Comptes rendus, 1906, 142, p. 400) by heating the hydride in a vacuum to 1000.
The hydride, SrH 2, was obtained by Guntz on heating strontium amalgam in a current of hydrogen.
The results given below, which are selected from a much larger series published in the Journal of the Chemical Society, were obtained by heating samples of the different coals in vacuo for several hours at the temperature of boiling water: - In one instance about i% of hydride of ethyl was found in the gas from a blower in a pit in the Rhondda district, which was collected in a tube and brought to the surface to be used in lighting the engine-room and pit-bank.
Although at the present time a marvellous improvement has taken place all round in the quality of the carbide produced, the acetylene nearly always contains minute traces of hydrogen, ammonia, sulphuretted hydrogen, phosphuretted hydrogen, silicon hydride, nitrogen and oxygen, and sometimes minute traces of carbon monoxide and dioxide.
The presence of free hydrogen is nearly always accompanied by silicon hydride formed by the combination of the nascent hydrogen with the silicon in the carbide.
Zirconium hydride, ZrH2, is supposed to be formed when zirconia is heated with magnesium in an atmosphere of hydrogen.
- Calcium hydride, obtained by heating electrolytic calcium in a current of hydrogen, appears in commerce under the name hydrolite.
Sodium hydride, NaH, is a crystalline substance obtained directly from sodium and hydrogen at about 400°.
They may also be prepared by eliminating the halogen hydride from the alkyl halides by heating with alcoholic potash, or with litharge at 220° C. (A.
It also combines directly with potassium hydride to form potassium formate (see Formic Acid).
The gas is rapidly absorbed by solutions of the caustic alkalis, with the production of alkaline carbonates (q.v.), and it combines readily with potassium hydride to form potassium formate.
Moissan (Comptes rend., 1902, 134, p. 261) prepared potassium formate by passing a current of carbon monoxide or carbon dioxide over heated potassium hydride, KH+CO 2 = Khco 2 and KH-F2CO = Khco2+C.
The compounds containing this radical are treated under other headings; the hydride is better known as ethane, the alcohol, C 2 H 5 OH, is the ordinary alcohol of commerce, and the oxide (C 2 H 5) 2 O is ordinary ether.
Buff carried out an inquiry on the compounds of silicon in which they prepared the previously unknown gas, silicon hydride or silicuretted hydrogen.
Hantzsch explains the characteristic reactions of the diazonium compounds ky the assumption that an addition compound is first formed, which breaks down with the elimination of the hydride of the acid radical, and the formation of an unstable syn-diazo compound, which, in its turn, decomposes with evolution of nitrogen (Ber., 18 97, 30, p. 2 54 8; 1898, 31, p. 2053).
Soc. chim., 1902, 27, p. 1141) has shown that potassium hydride decomposes cold water, with evolution of hydrogen, KH+H 2 0 = KOH+ H2.
Calcium hydride or hydrolite, prepared by passing hydrogen over heated calcium, decomposes water similarly, r gram giving 1 litre of gas; it has been proposed as a commercial source (Prats Aymerich, Abst.
Strontium hydride behaves similarly.
Phys., 18 74, (5) 2, p. 279) considered that a palladium hydride of composition Pd 2 H was formed, but the investigations of C. Hoitsema (Zeit.
It combines with water with evolution of heat, and on heating with magnesium powder in an atmosphere of hydrogen forms a hydride of probable composition La 2 H 3 (C. Winkler, Ber.
Rubidium hydride, RbH, was obtained in the form of colourless needles by H.
Cuprous hydride, (CuH) n, was first obtained by Wurtz in 1844, who treated a solution of copper sulphate with hypophosphorous acid, at a temperature not exceeding 70° C. According to E.
Merrill, it decomposes when heated, and gives cupric hydride, CuH 21 as a reddish-brown spongy mass, which turns to a chocolate colour on exposure.
Lithium hydride, LiH, obtained by heating the metal in a current of hydrogen at a red heat, or by heating the metal with ethylene to 700° C. (M.