| ≥1 piece |
|
Appearance |
White crystalline powder |
|
Assay |
99.0% ～ 101.0% |
|
Solubility in water |
Free soluble |
|
Solubility in alcohol |
Slightly soluble |
|
Ultraviolet absorption |
227 ± 2nm |
|
Test for potassium |
Positive |
|
Precipitation test |
Yellow precipitate |
|
Potassium |
17.0 ~ 21.0% |
|
Loss on drying |
≤ 0.5% |
|
Organic impurities |
≤ 20mg/kg |
|
Fluoride |
≤ 3mg/kg |
|
Heavy metals |
≤ 5mg/kg |
|
Lead |
≤ 1mg/kg |
|
Arsenic |
≤ 3mg/kg |
|
Selenium |
≤ 10mg/kg |
|
PH |
5.5 ~ 7.5 |