Q. What formula is COOH?

COOH is not a full formula by itself; it is a functional group known as the carboxyl group. It represents a combination of a carbonyl group (C=O) and a hydroxyl group (–OH) attached to the same carbon atom. This group is commonly written as –COOH in chemical structures.

The COOH group is a defining feature of carboxylic acids, which are widely found in biology and chemistry. For example, acetic acid (CH₃COOH) contains one COOH group, while amino acids contain both an amine group (–NH₂) and a carboxyl group (–COOH). Recognizing COOH helps identify acidic behavior and chemical reactivity in organic compounds.