Nitrogen combines with hydrogen to form ammonia, NH 3, hydrazine, N 2 H 4, and azoimide, N 3 H (qq.v.); the other known hydrides, N 4 H 4 and N5H5, are salts of azoimide, viz.
By the action of sodium amalgam on an alcoholic solution of anthracene, an anthracene dihydride, C14H12, is obtained, whilst by the use of stronger reducing agents, such as hydriodic acid and amorphous phosphorus, hydrides of composition C14H16 and C14H24 are produced.
Numerous hydrides are known; heated with red phosphorus and hydriodic acid the hydrocarbon yields mixtures of hydrides of composition C10H10 to C10H20.
It may be prepared by the electrolysis of acidulated water, by the decomposition of water by various metals or metallic hydrides, and by the action of many metals on acids or on bases.
Hydrogen combines with fluorine, even at very low temperatures, with great violence; it also combines with carbon, at the temperature of the electric arc. The alkali metals when warmed in a current of hydrogen, at about 360° C., form hydrides of composition RH(R = Na, K, Rb, Cs), (H.