Knowra Phosphorous acid Phosphorous acid Phosphorous acid (H₃PO₃) is an inorganic phosphorus oxoacid whose structure contains a direct phosphorus–hydrogen bond. It acts as a reducing agent and forms phosphite salts.
Phosphorous acid structure : The molecular arrangement of phosphorous acid, with one P–H bond and two P–OH groups. Only the two O–H hydrogens ionize readily; the P–H bond underlies reduction.
Phosphite fungicide : A crop-protection product based on phosphite salts, used especially against oomycete plant pathogens. Phosphorous acid is used to produce phosphite salts applied to crops.
Oxoacid : An acid containing oxygen, hydrogen, and another element, with acidic hydrogen commonly bonded through oxygen. Phosphorous acid belongs to this family, though one hydrogen is bonded directly to phosphorus.
Hypophosphorous acid : A phosphorus oxoacid with formula H₃PO₂, one hydroxyl group, and two phosphorus–hydrogen bonds. It has stronger reducing character than phosphorous acid because it contains two P–H bonds.
Phosphite : An anion or salt derived from phosphorous acid, commonly containing the HPO₃²⁻ ion. Loss of the two acidic O–H protons produces the phosphite ion.
Potassium phosphite : A potassium salt of phosphorous acid used in agricultural products and chemical formulations. It is a prominent formulated salt made from phosphorous acid.
Acid dissociation constant : A quantitative measure of an acid’s tendency to donate a proton in solution. Its two O–H protons dissociate in successive steps with distinct acid strengths.
Phosphine : A colorless, toxic phosphorus hydride with formula PH₃. Despite a related name and P–H bonds, it is a basic hydride rather than an oxoacid.
Phosphorus oxidation state : The formal electron-accounting value assigned to phosphorus in a chemical compound. Phosphorus is in the +3 oxidation state here and can be oxidized to +5.
Reducing agent : A substance that donates electrons to another substance and is itself oxidized. Phosphorous acid is valued in reactions where it supplies reducing power.
Show all 19