Silver hypophosphate, Ag₄P₂O₆

Silver nitrate gives with sodium hypophosphate, Na₄P₂O₆, a white precipitate of silver hypophosphate. It is also produced in crystalline form by boiling a solution of silver nitrate in nitric acid with phosphorus. Heat decomposes it into silver metaphosphate and metallic silver:

Ag₄P₂O₆ = 2AgPO₃ + 2Ag.