乙酸, also known as acetic acid, is a colorless liquid organic compound with a pungent smell. It is the main component of vinegar, which typically contains about 4-8% acetic acid. In its pure form, it is a strong acid and is used in various industrial processes, including the production of plastics, food additives, and solvents. In addition to its industrial uses, 乙酸 plays a role in the human body as a metabolic intermediate. It is involved in the synthesis of fatty acids and is important for energy production. Its chemical formula is C2H4O2, and it is classified as a carboxylic acid.