| 1 | Appearance/Description | Colorless crystals. | White or almost white powder or colorless crystals. | USP/Ph.Eur/BP |
| 2 | Solubility | Complies | Freely soluble in water; practically insoluble in ethanol (96%) | USP/Ph.Eur/BP |
| 3 | Identification (By chemical test) | Complies | Solution should be slightly alkaline | Ph.Eur/BP |
| 4 | Identification (By Loss on drying) | 19.98% | 19.5%- 21.0% | Ph.Eur/BP |
| 5 | Identification (Sodium) | Complies | A dense precipitate should form. | USP/Ph.Eur/BP |
| 6 | Identification (Phosphate 1) | Complies | A yellow precipitate that solution in 2N nitric acid and in 6N ammonium hydroxide should form. | USP |
| 7 | Identification (Phosphate 2) | Complies | With ammonium molybdate solution, acidified solutions should yield a yellow precipitate which should soluble in 6N ammonium hydroxide. | USP |
| 8 | Identification (Phosphate 3) | Complies | A yellow colour should develop | Ph.Eur/BP |
| 9 | Assay (on dry basis) | 98.89% | 98.0%- 100.5% | USP |
| 10 | Assay (Dried substance) | 98.95% | 98.0% -101.0% (Na2HPO4) | Ph.Eur/BP |
| 11 | Insoluble Substances | 0.3% | NMT 0.4% | USP |
| 12 | Appearance of solution | Complies | Clear and colorless solution | Ph.Eur/BP |
| 13 | Reducing substances | Complies | The color of the permanganate should not completely discharge | Ph.Eur/BP |
| 14 | Monosodium Phosphate | Less than 2.5% | NMT 2.5% | Ph.Eur/BP |
| 15 | Chlorides | Less than 400 ppm | NMT 400ppm | USP/Ph.Eur/BP |
| 16 | Sulphate (SO4) | Less than 0.1% | NMT 0.1% | USP/Ph.Eur/BP |
| 17 | Arsenic (As) | Less than 16 ppm | NMT 16 ppm | USP |
| 18 | Iron(Fe) | Less than 40 ppm | NMT 40 ppm | Ph.Eur/BP |
| 19 | Loss on drying,130°C | 19.98% | 19.5% - 21.0% | USP/Ph.Eur/BP |