Acid · C₂H₄O₂
The simplest carboxylic acid of industrial scale — vinegar's active component. Feedstock for vinyl acetate and acetic anhydride; a common process acid. Corrosive and hygroscopic.
| Formula | C₂H₄O₂ |
| CAS number | 64-19-7 |
| Synonyms | ethanoic acid, glacial acetic acid, AcOH |
| Molar mass | 60.05 g/mol (Computed from the molecular formula and CODATA atomic weights) |
| Normal boiling point | 117.9 °C (NIST Chemistry WebBook (webbook.nist.gov)) |
| Liquid density | 1049 kg/m³ (Reference liquid density near 20–25 °C (NIST WebBook)) |
Antoine equation (mmHg/°C): log₁₀(P) = 7.38782 − 1533.313 / (222.309 + T), valid 17–157 °C. Source: NIST Chemistry WebBook (webbook.nist.gov).
| °C | kPa | bar | mmHg | psia |
|---|---|---|---|---|
| 17.0 | 1.27 | 0.0127 | 9.6 | 0.185 |
| 45.0 | 5.98 | 0.0598 | 44.8 | 0.867 |
| 73.0 | 20.92 | 0.2092 | 156.9 | 3.034 |
| 101.0 | 58.91 | 0.5891 | 441.8 | 8.544 |
| 129.0 | 140.65 | 1.4065 | 1055.0 | 20.400 |
| 157.0 | 295.35 | 2.9535 | 2215.3 | 42.837 |
Using its Antoine constants (NIST Chemistry WebBook (webbook.nist.gov)), the saturation pressure of acetic acid at 25 °C is about 2.05 kPa. Use the calculator above for any temperature within 17–157 °C.
Acetic acid boils at 117.9 °C at atmospheric pressure (NIST Chemistry WebBook (webbook.nist.gov)). At that temperature its vapor pressure equals one atmosphere (760 mmHg).
Acetic acid (C₂H₄O₂, CAS 64-19-7) has a molar mass of 60.05 g/mol.