| ANALYTICAL ITEMS | SPECIFICATION |
| Appearance | White crystalline powder |
| Loss on drying | ≤1.0% |
| Residue on ignition | ≤ 0.2% |
| pH | 2.3~2.6 |
| Solubility | Very soluble in water |
| Melting point | 195°C~201°C |
| NH 4 | ≤ 0.01% |
| Heavy Metals (as Pb) | ≤10ppm |
| Arsenic | ≤1ppm |
| Assay | 98.0%~102.0% |