Physical Properties
Physical state at 20°C : Solid
Colour : White pellets
Odour : Odorless
pH value ................. 13 - 14
Melting point ........... 318 °C
Boiling point ............ 1390°C
Vapour pressure ..... < 24 hPa at 20 °C
Vapour density ........ >1
Density .................... 2.13 g/cm3
Solubility in water .... 111 g/100 g of water
Specifications
Appearance : White deliquescent pellets or pearls
Assay (acidimetric) .................. 98 - 100.5%
Identity ..................................... Passes test
(acc. to pharmacopoeias)
Appearance of solution ............ Passes test
Insoluble matter in water .......... Max 0.025%
Sodium carbonate (Na2CO3) ... Max 1.0%
Chloride (Cl) ............................. Max 0.005%
Sulphate (SO4) ........................ Max 0.003%
Phosphate (PO4) ..................... Max 0.001%
Silicate (SiO2) .......................... Max 0.001%
Total nitrogen (N) ...................... Max 0.0003%
Heavy metal (as Pb) ................ Max 0.002%
Iron (Fe) .................................... Max 0.001%
Nickel (Ni) ................................. Max 0.001%
Calcium (Ca) ............................. Max 0.005%
Potassium (K) ........................... Max 0.05%
Magnesium (Mg) ....................... Max 0.002%
Mercury (Hg) ............................. Max 0.00001%
