Phosphuretted hydrogen, one of the most important impurities, which has been blamed for the haze formed by the combustion of acetylene under certain conditions, is produced by the action of water upon traces of calcium phosphide found in carbide.
Calcium phosphide, Ca 3 P 2, is obtained as a reddish substance by passing phosphorus vapour over strongly heated lime.
A phosphide, PCr, is known; it burns in oxygen forming the phosphate.
Phosphorus combines directly with the metal to form W3P4; another phosphide, W2P, results on igniting a mixture of phosphorus pentoxide and tungsten.
The phosphide obtained by heating cupric phosphate, Cu 2 H 2 P 2 O 81 in hydrogen, when mixed with potassium and cuprous sulphides or levigated coke, constitutes " Abel's fuse," which is used as a primer.