| ITEM | STANDARD |
| Appearance | White crystalline powder |
| Assay | 99.0-101.0% |
| Odor | Absent |
| Water solubililty | Freely soluble |
| Ultraviolet absorption | 227±2NM |
| Solubility in ethanol | Slightly soluble |
| Loss on drying | 1.0 % max |
| Sul fate | 0.1% max |
| Potassium | 17.0-21 % |
| Impurity | 20ppm max |
| Heavy metal (pb) | 1.0ppm max |
| Fluorid | 3.0ppm max |
| Selenium | 10.0ppm max |
| Lead | 1.0ppm max |
| PH Value | 6.5-7.5 |








