Products Description of Phosphorous Acid
Phosphorous acid (H₃PO₃) is an inorganic chemical compound occurring as colorless to pale‑yellow ice‑like crystals. It dissolves readily in water and ethanol. Gradual oxidation takes place upon exposure to atmospheric air, yielding phosphoric acid. When heated up to 180 °C, it decomposes into orthophosphoric acid and phosphine gas. It features a melting point of 73 °C and a boiling point of 200 °C. As a key industrial raw material, phosphorous acid is primarily utilized for producing plastic stabilizers, and it also finds application in the manufacturing of synthetic fibers and phosphite salts.
Phosphorous acid Chemical Properties
| Melting point | 73 °C |
| Boiling point | 200 °C |
| density | 1.651 g/mL at 25 °C(lit.) |
| vapor pressure | 0.001Pa at 20℃ |
| Fp | 200°C |
| storage temp. | 0-6°C |
| solubility | DMSO (Slightly), Methanol (Slightly), Water (Sparingly) |
| form | Crystals |
| pka | pK1 1.29; pK2 6.74(at 25℃) |
| Specific Gravity | 1.651 |
| color | White |
| Water Solubility | SOLUBLE |
| Sensitive | Air Sensitive & Hygroscopic |
| Merck | 147346 |
| Stability: | Stable. Incompatible with strong bases. Hygroscopic. |
| CAS DataBase Reference | 13598-36-2(CAS DataBase Reference) |
| NIST Chemistry Reference | (HO)2HPO(13598-36-2) |
| EPA Substance Registry System | Phosphonic acid (13598-36-2) |
| Hazard Codes | C |
| Risk Statements | 22-35 |
| Safety Statements | 26-36/37/39-45 |
| RIDADR | UN 2834 8/PG 3 |
| WGK Germany | 1 |
| RTECS | SZ6400000 |
| F | 3 |
| TSCA | Yes |
| HazardClass | 8 |
Product Application of Phosphorous Acid CAS#13598-36-2
Phosphorous acid serves as an essential raw material for manufacturing phosphite salts, plastic stabilizers such as dibasic lead phosphite, and organophosphorus‑based pesticides. Besides, it can function as a stabilizer for polycarbonate and act as an antioxidant additive for Nylon‑1010 polymer.
