Hypophosphorous acid is a phosphorus oxoacid and a powerful reducing agent with molecular formula H3PO2. It is a colorless low-melting compound, which is soluble in water, dioxane, and alcohols.Hypophosphorous acid is also used in the formulation of pharmaceuticals, discoloration of polymers, water treatment, retrieval of precious or non-ferrous metals.Its main industrial use is for electroless nickel plating (Ni–P), although it is primarily used as a salt (sodium hypophosphite)