Hypophosphorous acid

Phosphonous acid is a phosphorus oxoacid.

Hypophosphorous acid is a powerful reducing agent with a molecular formula of H3PO2. Inorganic chemists refer to the free acid by this name although its IUPAC name is dihydridohydroxidooxidophosphorus, or the acceptable name of phosphinic acid. It is a colorless low-melting compound, which is soluble in water, dioxane, and alcohols. The formula for hypophosphorous acid is generally written H3PO2, but a more descriptive presentation is HOP(O)H2 which highlights its monoprotic character. Salts derived from this acid are called phosphinates (hypophosphites).

This acid has the general formula ofH4P2O6 and differs from the other oxy-phosphorous acids. It has many peculiarities. It is formed along with phosphorous and phosphoric acids, when phosphorus is oxidized by moist air. If white phosphorus is exposed to air, and sodium acetate is addedto the liquidwhich forms, the somewhat insoluble sodium hypophosphate,Na2H2P2O6·6H2Oseparates. The sodium hypophosphate monohydrate, however, is very soluble and deliquescent at ～98.7 g/100 ml.

colourless liquid

ChEBI: A phosphorus oxoacid that consists of a single pentavalent phosphorus covalently bound via single bonds to two hydrogens and a hydroxy group and via a double bond to an oxygen. The parent of the class of phosphinic acids.

1. Hypophosphorous acid is used as reducing agent for electroless plating;2. It can be used to prevent discoloration of phosphoric acid resin;3. It is used as esterification catalyst, the refrigerant;4. It is used to produce hypophosphite, sodium salts, manganese salts, iron salts are generally used as nourishing substances;5. Hypophosphorous acid is used in medicine and as reducing agent, the determination of arsenic, tellurium and separation of tantalum, niobium and other reagents.6. It is strong reducing agent, It can be used for the preparation of sodium hypophosphite, calcium phosphate and other hypophosphite.7. It can be used for the plating bath. Pharmaceuticals. reducing agent. general reagents.8. It is strong reducing agent, it can be used in making sodium hypophosphite, calcium phosphate and other hypophosphite.9. This product is widely used as reducing agent, Ag, Cu, Ni, Hg and other metals are reduced to the corresponding metal, for the verification of As, Nb, Ta and other reagents, it can be used for the preparation of Na, K, Ca, Mn, Fe and other types of hypophosphite.

Hypophosphorous acid is primarily used for electroless nickel plating. It is involved in the reduction of arenediazonium salts. It acts as an additive in Fischer esterification reactions. Also, it serves as a neutralizing agent, antioxidant, catalyst in polymerization and poly condensation, and wetting agent. Further, it is used in the formulation of pharmaceuticals, discoloration of polymers, water treatment and retrieval of precious or non-ferrous metals. In addition to this, it is used as bleaching agents for plastics, synthetic fibers, decolorizing agent and for color stabilization during the manufacture of chemicals and several plastics.

Hypophosphorous acid is formed by reaction of barium hypophosphite and sulfuric acid, and filtering off barium sulfate. By evaporation of the solution in vacuum at 80 °C, and then cooling to 0°C, hypophosphorous acid crystallizes.