Potassium Nitrate
Potassium Nitrate | BP | REFINED |
Description | White or almost white crystalline powder or colorless crystals | White crystalline powder |
Identification | It gives reactions of nitrates and of potassium | It gives reactions of nitrates and of potassium |
Solubility | Freely soluble in water, very soluble in boiling water, practically insoluble in ethanol (96%) | Highly soluble in water |
Appearance of solution | Clear and colorless | Clear and colorless |
K2O | - | 46.44% |
Insoluble matter | - | Max 0.02% |
Alkalinity/Acidity | Not more than 0.5 ml of 0.01 m HCl or 0.5 ml of 0.01 M NaOH | |
Residual Substance | Solution does not become blue within 2 min | |
Heavy Metals | Max 10 ppm | Max 0.002% |
Sodium | Max 0.1% | |
Chloride | Max 20 ppm (if intended for ophthalmic use) | Max 0.07% |
Iron | Max 20 ppm | |
Ammonia | Max 100 ppm | |
Sulphate | Max 150 ppm | Max 0.03% |
Loss on Drying | Max 0.5% | |
Calcium & Magnesium | Max 100 ppm (Cal) | Max 0.05% |
Nitrogen | - | 13.82% |
pH | - | 6.0 to 8.0 |
Moisture | - | Max 1.0% |
Assay dry basis | 99.0% to 101.0% | Min 99.72% |