Item
Standard
Result
Identification
Positive
Complies
Melting point of °C
226-230
227.2-229.5
Appearance
White crystal
Content%
99.0-101.0
99.58
Water%
≤15
13.92
Ammonium Salts
≤25ppm
15ppm
Heavy metals
≤10ppm
5ppm
Arsenic
≤2ppm
0.1ppm
Lead
Free acid or alkali
Complies with BP/USP/EP
Benzoate and salicylate
No precipitate or violet color appears
Readily carbonizable substances
Not more intensely colored than reference
P-Toluene sulfonamide
6ppm
O-Toluene sulfonamide
Selenium
≤30ppm
Benzoic acid-sulfonamide
Solubility
Freely soluble in water, sparingly soluble in ethanol
Clarity and color of solution
Colorless, clear