Discover key carboxylic acid properties , structure, and uses with examples. Learn physical & chemical characteristics for exams and real-life relevance. A carboxylic acid is an organic compound that contains a carboxyl functional group (-COOH). This special group is made of a carbonyl group (C=O) and a hydroxyl group (-OH) attached to the same carbon atom. This structure is what gives them their characteristic acidic properties. Carboxylic acid Structure of a carboxylic acid Carboxylate anion 3D structure of a carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group (−C (=O)−OH) [1] attached to an R-group. Learn about the structure, classification, properties and reactions of carboxylic acids and their derivatives, such as esters, amides, anhydrides and acyl chlorides. Find examples, formulas, mechanisms and reactivity orders of these organic compounds.