etaanhappo

Etanohappo, or ethanoic acid (commonly known in English as acetic acid), is the simplest carboxylic acid with two carbon atoms. Its chemical formula is CH3COOH. It is a colorless, corrosive liquid with a characteristic sour, pungent odor, most familiar in dilute form as vinegar, which contains typically 4–8% acetic acid by weight.

Natural occurrence and properties

Etanohappo occurs widely in nature and is produced by fermentation processes. In vinegar, acetic acid is formed by the oxidation of ethanol by acetic acid bacteria. Pure acetic acid freezes at 16.6 °C and boils at 118.1 °C, with a density of about 1.049 g/mL at 25 °C. The acid dissociation constant (pKa) is about 4.76, reflecting its weak acid character. It is miscible with water and many organic solvents and serves as both a reagent and a solvent in chemical synthesis.

Production and industrial use

Industrially, acetic acid is produced primarily by carbonylation of methanol (the Monsanto and Cativa processes), yielding high-purity acetic acid. An older route involves oxidation of acetaldehyde. Acetic acid is a key chemical feedstock and solvent, and it is also a food additive (E260) used as an acidity regulator and preservative. It is a precursor for many derivatives, including acetic anhydride, esters such as ethyl acetate, and polymers like polyvinyl acetate.

Safety and handling

Etanohappo is corrosive to skin, eyes, and mucous membranes and can irritate the respiratory tract. Concentrated vapors and liquids should be handled with appropriate protective equipment in a well-ventilated area. It is typically stored in corrosion-resistant containers. In case of contact or ingestion, seek immediate medical attention and follow established safety guidelines.