Appearance : White powder Melting point 216~219℃ Acidity : PH of 4.0-6.0 Loss on drying: <1.0% Heavy Metals(Pb): <200ppm Residue on ignition: <0.2% Chloride: <200ppm Sulfate : <500ppm Related Substances: <0.1% Assay: Not less than 99.0% C6H6O3, Calculated by the dry product.