1 | Description | White, crystalline powder. Is odorless and is slightly deliquescent. Its solutions are acid to litmus and effervesce with sodium carbonate | Colorless crystals or white, crystalline powder.Is odorless and is slightly deliquescent. Its solutions are acid to litmus and effervesce with sodium carbonate |
2 | Solubility | Complies | Freely soluble in water; practically insoluble in alcohol. |
3 | Identification A (Sodium) | Complies | A dense precipitate should form. |
4 | Identification B (Phosphate 1) | Complies | A neutral solution should yield yellow precipitate that soluble in 2N nitric acid and 6 N ammonium hydroxide |
5 | Identification B (Phosphate 2) | Complies | With ammonium molybdate solution, acidified solutions should yield a yellow precipitate that should soluble in 6N ammonium hydroxide. |
6 | Assay (Anhydrous basis) | 98.8% | 98.0% - 103.0% |
7 | Insoluble Substances | 0.003% | NMT 0.2% |
8 | Chlorides | Less than 0.014% | NMT 0.014% |
9 | Sulphate (SO4) | Less than 0.15% | NMT 0.15% |
10 | Aluminium, Calcium and Related Element | Complies | The sample solution should not become turbid when rendered slightly alkaline to litmus paper with 6N ammonium hydroxide. |
11 | Arsenic (As) | Less than 8ppm | NMT 8ppm |
12 | pH | 4.3 | 4.1 -4.5 |
13 | Water | 0.5% | NMT 2.0% |