Appearance White crystalline powder White crystalline
Assay 99.0%Min 99.90%
Melting point 203-206degree 204.6-205.8
Clarity of water solution Transpency, colorless, none suspended matters Pass
pH value of 1% aqueous solution 5.0-7.0 6.05
Specific optical ratation D20=+176~184degree +179.5
Arsenic 2 ppm max pass
Hydroquinone 10 ppm max pass
Heavy metal 10 ppm max pass
Loss on drying 0.5% max 0.05%
Ignition residue 0.5% max 0.04%
Pathogen Bacteria:300cfu/g max
Fungus:100cfu/g max 20
20
Conclusion pass