Acetic acid
Molar mass: 60.05 g/mol · Class: Weak carboxylic acid
Elements: carbon, hydrogen, oxygen
Structure
The molecule has a methyl group (CH3) bonded to a carboxyl group (-COOH). The hydrogen on the carboxyl group is the acidic one; it is released in water to give the acetate ion.
Properties
Weak acid: only partly ionizes in water
Pungent vinegar smell; pure form is called glacial acetic acid
Miscible with water in all proportions
Corrosive to skin and eyes when concentrated
Applications
Vinegar for food and pickling
Manufacture of plastics, fibers, and adhesives
Household descaler and cleaner (dilute)
Photography and textile processing
Vinegar (5%) is food-safe, but concentrated acetic acid burns skin and eyes and its vapors irritate lungs. Never mix vinegar with bleach. Keep concentrated forms locked away from children.
Data source: IUPAC standard atomic weights 2021; molar mass computed from CH3COOH