Sodium hypophosphite monohydrate (sodium phosphinate monohydrate)
| Formula | H2NaO2P*H2O |
| Chemical formula | NaH2PO2*H2O |
| Density | 1.18 g/cm3 (20°C) |
| Molar mass | 105.99 g/mol |
| Bulk density | ~ 1000 kg/m3 |
| CAS number | 10039-56-2 |
| HS Code | 28351000 |
| EC number | 231-669-9 |
| Storage | Without limitation |
| SDS | available |
| RTECS | SZ5640000 |
| Odour | odourless |
| Form | crystal |
| Color | white |
| p H | 6.0 – 8.0(10g/l ) |
| Solubility in water | 1100g/l (20°C) |
| Solubility in ethanol | soluble(20°C) |
| Vapour pressure | 30 hPa (20 °C) |
| Thermal decomposition | >248 °C |
| Assay | 97.0 – 103.0 | % | |
| Description | Conforms | ||
| Identification | Conforms | ||
| Appearance of solution | Conforms | ||
| Acidic substances | Conforms | ||
| Chloride | ≤ | 0/02 | % |
| Phosphate/Phosphite | Conforms | ||
| Heavy metals | ≤ | 0/0005 | % |
| Calcium | ≤ | 0/02 | % |
| Iron | ≤ | 0/0005 | % |
Sodium hypophosphite monohydrate is an inorganic compound consisting of sodium and hypophosphite ions, widely used as a strong reducing agent in electroless nickel plating and chemical synthesis.
🏭⚗️ Production
It is produced industrially by reacting white phosphorus with alkaline solutions to form hypophosphorous acid, which is then neutralized with sodium hydroxide. In laboratory settings, it is prepared by neutralizing hypophosphorous acid with sodium hydroxide followed by crystallization.
🔬 Properties
Sodium hypophosphite monohydrate appears as a white crystalline powder, highly soluble in water. Its chemical formula is NaH₂PO₂·H₂O with a molar mass of about 106 g/mol. It is stable under normal conditions but decomposes on heating to release toxic and flammable phosphine gas.
🧪 Applications
It is mainly used in electroless nickel plating, pharmaceuticals, polymer stabilization, and as a reducing agent in labs.
⚠️ Safety
Sodium hypophosphite monohydrate should be handled carefully due to the release of toxic phosphine gas upon heating. It is harmful if ingested, inhaled, or comes in contact with skin and eyes. Proper protective equipment and storage away from heat and oxidizers are necessary.
