| Property | Specification |
| Appearance | Colorless to slightly yellow liquid |
| Odor | Odorless or slight acidic odor |
| Molecular Formula | H?PO? |
| Molecular Weight | 98.00 g/mol |
| Density | 1.57 g/cm³ (at 25°C) |
| Boiling Point | 158°C (316.4°F) |
| Melting Point | 42.35°C (108.23°F) |
| Solubility | Soluble in water |
| Viscosity | 1.3–1.6 mPa·s (at 25°C) |
| Refractive Index | 1.457 (at 25°C) |
| pH (1% solution) | 1.0–2.0 |
