Cobalt nitroprusside, Co[Fe(CN)₅NO]

Cobalt nitroprusside, Co[Fe(CN)₅NO], obtained by double decomposition of a soluble cobalt salt with sodium nitroprusside, is a red salt, possessing an appreciable solubility in water. It dissolves in acids, but is insoluble in potassium hydroxide or ammonia solution. This latter property enables it to be separated from the corresponding nickel salt, which readily dissolves in ammonia.