Acetic acid.
Acetic acid [64-19-7].

Packaging and storage— Preserve in tight containers.

Identification— It responds to the tests for Acetate 191.

Nonvolatile residue— Evaporate 20 mL in a tared porcelain dish on a steam bath, and dry at 105 for 1 hour: the weight of the residue does not exceed 1.0 mg (0.005%).

Chloride— Add 5 drops of silver nitrate TS to 10 mL of a solution (1 in 10): no opalescence is produced.

Sulfate— Add 5 drops of barium chloride TS to 10 mL of a solution (1 in 10): no turbidity is produced.

Heavy metals 231— To the residue obtained in the test for Nonvolatile residue add 8 mL of 0.1 N hydrochloric acid, warm gently until solution is complete, dilute with water to 100 mL, and use 10 mL of the solution: the limit is 0.001%.

Readily oxidizable substances— Dilute 4.0 mL in a glass-stoppered vessel with 20 mL of water, and add 0.30 mL of 0.10 N potassium permanganate: the pink color is not changed to brown at once, and the liquid does not become entirely brown or free from a pink tint in less than 30 seconds.

Assay— Place about 6 mL of Acetic Acid in a tared, glass-stoppered flask, and weigh accurately. Add 40 mL of water, then 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.

Topic/Question	Contact	Expert Committee
Monograph	Feiwen Mao, M.S. Scientist 1-301-816-8320	(MDOOD05) Monograph Development-Ophthalmics Oncologics and Dermatologicals

USP32–NF27 Page 1151

ACETIC ACID

Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.