|
Appearance
|
White crystalline powder
|
|
Assay (acidimetric)
|
99.5 - 101%
|
|
Carbonate
|
The pH of freshly prepared 5% solution is not greater than 8.6
|
|
Chloride (Cl)
|
Max 0.015%
|
|
Sulphate (SO4)
|
Max 0.01%
|
|
Arsenic (As)
|
Max 0.0002%
|
|
Heavy metal (as Pb)
|
Max 0.0005%
|
|
Calcium (Ca)
|
Max 0.005%
|
|
Iron (Fe)
|
Max 0.001%
|
|
Copper (Cu)
|
Max 0.0005%
|
|
Sodium (Na)
|
Max 0.5%
|
|
Zinc (Zn)
|
Max 0.0025%
|
|
Loss on drying (over silica gel)
|
Max 0.3%
|