Ruthenium Silicide, RuSi

Ruthenium Silicide, RuSi, results on heating a mixture of finely divided ruthenium and crystallised silicon in the electric furnace. The product is crushed and treated successively with alkali and a mixture of hydrofluoric and nitric acids. The silicide together with carborundum remains behind. The two may be separated with methylene iodide on account of the high density of ruthenium silicide, namely, 5.4.

Ruthenium silicide is a very hard, white substance, of great stability. It volatilises in the electric arc. Chlorine slowly attacks it, fluorine readily. It burns in oxygen at high temperatures, and is decomposed by sulphur vapour at red heat. Boiling acids do not affect it.