Carbon dioxide, recognized by turning lime-water milky, indicates decomposable carbonates or oxalates.
Chlorine, bromine, and iodine, each recognizable by its colour and odour, result from decomposable haloids; iodine forms also a black sublimate.
Cyanogen and hydrocyanic acid, recognizable by their odour, indicate decomposable cyanides.
To form (1) oxides and nitric acids, (2) ammonia, (3) readily decomposable nitrides, (4) cyanides, (5) cyanamides.
Mehner patented heating the oxides of silicon, boron or magnesium with coal or coke in an electric furnace, and then passing in nitrogen, which forms, with the metal liberated by the action of the carbon, a readily decomposable nitride.