| 1 | Appearance | Colourless, crystals, efflorescent. | White or almost white, crystalline powder, colourless crystals or granules, efflorescent.(Note: The product may cause lumps or hardening over the storage). |
| 2 | Solubility | Complies | Very soluble in water, freely soluble in ethanol (96%) |
| 3 | Identification A (By IR) | Complies | IR spectra of the sample should be concomitant with IR spectra of the corresponding standadrd |
| 4 | Identification B (By Water) | 8.5% | 7.5% to 9.0% |
| 5 | Appearance of Solution | Complies | The solution is clear and colourless or not more intensely coloured than reference solution Y7, BY7 or GY7. |
| 6 | Readily carbonizable substances | Complies | The solution is not more intensely coloured than a mixture of 1ml of red primary solution and 9ml of yellow primary solution. |
| 7 | Oxalic acid | Less than 360ppm | NMT 360ppm (Calculated as anhydrous oxalic acid) |
| 8 | Sulfates | Less than 150ppm | NMT 150ppm |
| 9 | Water | 8.5% | 7.5% to 9.0% |
| 10 | Sulphated ash | 0.06% | Not more than 0.1% |
| 11 | Assay (Anhydrous basis) | 99.8% | 99.5%-100.5% |