Carboxylic acids contain carbonyl group but do not show the nucleophilic addition reaction like aldehydes or ketones. Why?
Carboxylic acid doesnt show nucleophilic substitution reaction as because the presence of lone pair atoms on O atom of OH group decreases electrophilic character of carbonyl carbon by resonance. Hence, the partial positive charge decreases, and therefore it doesn't show nucleophilic substitution reactions.