Testing Item

Standard

Testing Result

Appearance

White or almost white crystalline powder or colourless crystals 

Almost white crystalline powder 

Identification

IR characteristic reaction and test of chlorides 

Confirm

Assay

98.0% to 102.0%

99.7%

Absorbance of solution

0.025 max

0.020

PH

2.7 to 3.4

3.1

Limit of Nitrate

No brown ring is produced 

Confirm

Water

5.0% max.

1.2%

Residue on ignition

0.2% max

0.04%

Chromatographic purity

1.0%max 

0.1%

Residual substances 

Any impurity 

0.4% max

0.1%

Total 

1.0% max

0.3%