| 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). | Ph.Eur |
| 2 | Solubility | Complies | Very soluble in water, freely soluble in ethanol (96%) | Ph.Eur |
| 3 | Identification A (By IR) | Complies | IR spectra of the sample should be concomitant with IR spectra of the corresponding standadrd | Ph.Eur |
| 4 | Identification B (By Water) | 8.35% | 7.5% to 9.0% | Ph.Eur |
| 5 | Appearance of Solution | Complies | The solution should be clear and colourless or not more intensely coloured than reference solution Y7, BY7 or GY7. | Ph.Eur |
| 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. | Ph.Eur |
| 7 | Oxalic acid | Less than 360 ppm | NMT 360ppm (Calculated as anhydrous oxalic acid) | Ph.Eur |
| 8 | Sulfates | Less than 150 ppm | NMT 150ppm | Ph.Eur |
| 9 | Water | 8.35% | 7.5% to 9.0% | Ph.Eur |
| 10 | Sulphated ash | 0.05% | NMT 0.1% | Ph.Eur |
| 11 | Assay (Anhydrous basis) | 99.8% | 99.5%-100.5% | Ph.Eur |