CH₃COOH
Compound · Acid
Acetic acid
乙酸 (醋酸)
Acetic acid (乙酸 (醋酸)), formula CH₃COOH, is a acid with a molar mass of 60.05 g/mol (CAS 64-19-7). Colourless pungent liquid; pure acid freezes near room temperature; miscible with water and ethanol.
Key facts
| Molar mass | 60.05 g/mol |
|---|---|
| Category | Acid |
| State at 25°C | Liquid |
| CAS | 64-19-7 |
Structure
CH₃–C(=O)–OH
Organic weak acid bearing a carboxyl –COOH group
Physical properties
| Appearance | Colourless pungent liquid; pure acid freezes near room temperature |
|---|---|
| Melting point | 16.6 °C |
| Boiling point | 118 °C |
| Density | 1.05 g/cm³ |
| Solubility | Miscible with water and ethanol |
Key reactions
CH₃COOH ⇌ CH₃COO⁻ + H⁺
Weak acid, only partially ionised
2CH₃COOH + Na₂CO₃ → 2CH₃COONa + H₂O + CO₂↑
Reacts with carbonates, releasing CO₂
CH₃COOH + C₂H₅OH ⇌ CH₃COOC₂H₅ + H₂O
Esterification with ethanol gives ethyl acetate
Main uses
- Main component of vinegar
- Feedstock for vinyl acetate and cellulose acetate
- Solvent and food preservative
Hazard
ModerateConcentrated (glacial) acid is corrosive; vapour is irritating
Constituent elements
Data sources
Molar mass is computed from IUPAC (CIAAW) standard atomic weights; formula, properties and reactions can be verified on PubChem, NIST and Wikipedia. The CAS number is the substance's unique registry identifier. Educational reference only.