Item

Standard

 Appearance

White to cream powder

 pH

2.3～2.4

Melting Point

158℃～163℃

Optical rotation

+186.0°～+188.0°

Loss on drying

≤1.0%

Residue on ignition

≤0.2%

Free ascorbic acid

≤0.1%

Free glucose

≤0.1%

Heavy metals（pb）

≤10ppm

Arsenic(AS2O3)

≤1ppm

Assay

≥98.0%

purity

≥99.5%