Acetic acid, systematically named ethanoic acid, is an acidic, colourless liquid and organic compound with the chemical formula CH₃COOH. Vinegar is at least 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water and other trace elements.Formula: CH₃COOHIUPAC ID: Acetic acidMolar mass: 60.052 g/molBoiling point: 118 °CDensity: 1.05 g/cm³Melting point: 16.6 °C