Diluted Acetic Acid
» Diluted Acetic Acid is a solution containing, in each 100 mL, not less than 5.7 g and not more than 6.3 g of acetic acid (C2H4O2). Prepare Diluted Acetic Acid as follows (see Pharmaceutical Compounding—Nonsterile Preparations 795):
Acetic Acid 158 mL
Purified Water, a sufficient quantity to make 1000 mL
Mix the ingredients.
Packaging and storage— Preserve in tight containers.
Identification— It meets the requirements of the tests for Acetate 191.
Heavy metals, Method I 231 Evaporate 5 mL in a porcelain dish on a steam bath to dryness. Warm the residue with 2 mL of 1 N acetic acid, and dilute with water to 50 mL. Dilute 20 mL of this solution with water to 25 mL: not more than 0.001% is found.
Readily oxidizable substances— To 20 mL in a glass-stoppered flask add 0.30 mL of 0.10 N potassium permanganate: the pink color is not changed to brown immediately, and the liquid does not become entirely brown or free from a pink tint in less than 30 seconds.
Limit of nonvolatile residue— Evaporate 20 mL in a tared porcelain dish on a steam bath, and dry it at 105 for 1 hour: the weight of the residue does not exceed 1.0 mg. Not more than 0.005% is found.
Limit of chloride— Add 5 drops of silver nitrate TS to 10 mL of a solution (6 in 10): no opalescence is found.
Limit of sulfate— Add 5 drops of barium chloride TS to 10 mL of a solution (6 in 10): no turbidity is produced.
Assay— Transfer 25.0 mL of Diluted Acetic Acid to a flask, and add 15 mL of carbon dioxide–free water. Add phenolphthalein TS, and titrate with 1 N sodium hydroxide VS. Each mL of 1 N sodium hydroxide is equivalent to 60.05 mg of C2H4O2.
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