Phosphorous acid is the compound described by the formula H₃PO₃. This acid is diprotic, not triprotic as might be suggested by this formula. Phosphorous acid is an intermediate in the preparation of other phosphorus compounds.
How do you make a phosphorous acid?
On an industrial scale, the acid is prepared by hydrolysis of phosphorus trichloride with water or steam: PCl3 + 3 H2O → HPO(OH)2 + 3 HCl.
Is phosphonic acid the same as phosphoric acid?
Key Difference – Phosphorus vs Phosphoric Acid
The key difference between Phosphorus and phosphoric acid is that Phosphorus acid (IUPAC name: Phosphonic acid) is diprotic whereas phosphoric acid (IUPAC name: Trihydroxidooxidophosphorus) is triprotic.
