Glacial Acetic Acid

C2H4O2 60.05
Acetic acid

[64-19-7].

DEFINITION

Glacial Acetic Acid contains NLT 99.5% and NMT 100.5%, by weight, of C2H4O2.

IDENTIFICATION

• Identification Tests—General, Acetate

191

: Meets the requirements

Sample solution (for lanthanum nitrate test): Glacial Acetic Acid and water (1:100)

ASSAY

• Procedure

Sample solution: Measure 2 mL of Glacial Acetic Acid into a glass-stoppered flask, previously tared while containing about 20 mL of water, and weigh again to obtain the weight of the substance under assay.

Analysis: Add 20 mL of water, then add phenolphthalein TS. Titrate with 1 N sodium hydroxide VS. Each mL of 1 N sodium hydroxide is equivalent to 60.05 mg of C2H4O2.

Acceptance criteria: 99.5%–100.5%

IMPURITIES

Inorganic Impurities

• Limit of Nonvolatile Residue: Evaporate 20 mL in a tared dish, and dry at 105

for 1 h: the weight of the residue does not exceed 1.0 mg.

• Heavy Metals

231

: NMT 5 ppm

Sample solution: To the residue obtained in the test for Limit of 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 20 mL.

• Chloride and Sulfate, Chloride

221

Sample solution: Dilute 1.0 mL with 20 mL of water.

Analysis: Add 5 drops of silver nitrate TS.

Acceptance criteria: No opalescence is produced.

• Chloride and Sulfate, Sulfate

221

Sample solution: Dilute 1.0 mL with 10 mL of water.

Analysis: Add 1 mL of barium chloride TS.

Acceptance criteria: No turbidity is produced.

Organic Impurities

• Procedure: Readily Oxidizable Substances