| ≥1 piece |
| Appearance | White or almost white, crystalline powder or colourless crystals |
| Melting Point |
About 190℃, with decomposition |
| Identification | Positive reaction |
|
pH (with 5% water solution) |
2.1 ~ 2.6 |
|
pH (with 2% water solution) |
2.4 ~ 2.8 |
|
Appearance of solution |
Clarity : clear; Colour: ≤BY7 |
|
Specific optical rotation |
+20.5º~ +21.5º |
|
Loss on drying |
≤0.4% |
|
Impurity E |
≤0.2% |
|
Related substance |
Impurity C: ≤0.15% Impurity D: ≤0.15% Unspecified impurities: ≤0.10% Total impurities: ≤0.2% |
|
Copper |
≤5.0ppm |
|
Iron |
≤2.0ppm |
| Arsenic | ≤3.0ppm |
|
Lead |
≤2.0ppm |
|
Mercury |
≤1.0ppm |
|
Cadmium |
≤1.0ppm |
|
Heavy metals |
≤10ppm |
|
Sulphated ash |
≤0.1% |
|
Residual solvents |
Meets the requirement |
|
Assay |
99.0%~100.5% |