Carboxylic Acids When a carbonyl carbon also bears a hydroxyl group,then these compounds are appreciably acidic,and are called carboxylic acids. 0 R-C-O-H RCOH RCOOH Carboxylic acids are classified according to the substituent that is bonded to the carboxyl carbon: Aliphatic acids have an alkyl group bound to the carboxyl group. An aromatic acid has an aryl group bound to the carboxyl group 0 H-C-O-H CH:-CH,-C- -O-H C一O-H CH,(CH)6一C-O-H formic acid propionic acid benzoic acid stearic acid (an aliphatic acid) (an aromatic acid) (a fatty acid) ◆20aP3 Edicaton he The simplest acid is formic acid. A carboxylic acid donates protons by the heterolytic cleavage of the O-H bond,generating a carboxylate ion 0 H-C-O-H H H-C-O Ch20 Carboxylic Acids (landscape) PageICh20 Carboxylic Acids (landscape) Page 1 Carboxylic Acids When a carbonyl carbon also bears a hydroxyl group, then these compounds are appreciably acidic, and are called carboxylic acids. Carboxylic acids are classified according to the substituent that is bonded to the carboxyl carbon: Aliphatic acids have an alkyl group bound to the carboxyl group. An aromatic acid has an aryl group bound to the carboxyl group. The simplest acid is formic acid. A carboxylic acid donates protons by the heterolytic cleavage of the O-H bond, generating a carboxylate ion. R C O O-H RCO2H RCOOH H C O O-H H C O O H + -