Chapter 20 ? 2010, Prentice Hall Organic Chemistry, 7th Edition L. G. Wade, Jr. Carboxylic Acids Chapter 20 * Introduction The functional group of carboxylic acids consists of a C?O with ?OH bonded to the same carbon. Carboxyl group is usually written ?COOH. Aliphatic acids have an alkyl group bonded to ?COOH. Aromatic acids have an aryl group. Fatty acids are long-chain aliphatic acids. Chapter 20 Chapter 20 * Common Names Many aliphatic acids have historical names. Positions of substituents on the chain are labeled with Greek letters starting at the carbon attached to the carboxylic carbon. Chapter 20 Chapter 20 * IUPAC Names Remove the final -e from alkane name, add the ending -oic acid. The carbon of the carboxyl group is #1. Chapter 20 Chapter 20 * Unsaturated Acids