Packaging and storage
Preserve in tight, light-resistant containers.
Identification
B:
A solution (1 in 50) reduces alkaline cupric tartrate TS slowly at room temperature but more readily upon heating.
Specific rotation
781S
:
between +20.5
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and +21.5
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, the optical rotation being measured immediately, following the preparation of the solution.
Test solution:
100 mg per mL, in carbon dioxide-free water.
Organic volatile impurities, Method IV
467
:
meets the requirements.
Assay
Dissolve about 400 mg of Ascorbic Acid, accurately weighed, in a mixture of 100 mL of water and 25 mL of 2 N sulfuric acid. Add 3 mL of starch TS, and titrate at once with 0.1 N iodine VS. Each mL of 0.1 N iodine is equivalent to 8.806 mg of C6H8O6.