Ascorbic Acid, Form : Powder

item

standard

appearance

white or almost white crystal or crystalline powder

melting point 

191 °c ~ 192°c 

ph (5%, w/v)   

  2.2 ~ 2.5 

ph (2%,w/v)   

  2.4 ~ 2.8 

specific optical rotation  

  +20.5° ~ +21.5°  

clarity of solution 

  clear 

heavy metals 

  ≤0.0003% 

assay (as c 6h 8o6, %)  

  99.0 ~ 100.5 

copper 

  ≤3 mg/kg

iron 

  ≤2 mg/kg

loss on drying 

  ≤0.1%

sulphated ash 

  ≤ 0.1%

residual solvents (as methanol) 

   ≤ 500 mg/kg  

total plate count (cfu/g) 

  ≤ 1000

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