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Appearance
|
White hygroscopic crystalline powder
|
|
Assay (acidimetric; on dried basis)
|
98 - 100.5%
|
|
pH (10% solution in water)
|
8.5 - 9.6
|
|
Appearance of solution
|
Passes test
|
|
Insoluble matter in water
|
Max 0.2%
|
|
Carbonate
|
Passes test
|
|
Chloride (Cl)
|
Max 0.02%
|
|
Fluoride (F)
|
Max 0.001%
|
|
Sulphate (SO4)
|
Max 0.1%
|
|
Heavy metal (as Pb)
|
Max 0.001%
|
|
Iron (Fe)
|
Max 0.001%
|
|
Arsenic (As)
|
Max 0.0002%
|
|
Sodium (Na)
|
Max 0.5%
|
|
Potassium hydrogen phosphate (KH2PO4)
|
Max 3.0%
|
|
KMnO4 reducing matter (as O)
|
Max 0.04%
|
|
Loss on drying (at 130°C)
|
Max 1%
|