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How does a carboxylic acid donate a hydrogen ion to a base?

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oxidation of alcohols — carboxylic acid Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.

A carboxylic acid donates a hydrogen ion ( $H^{+}$ ), also known as a proton, to a base through a process of direct proton transfer.12

In this chemical reaction, the carboxylic acid (represented by the general formula $R C O O H$ ) loses the hydrogen atom attached to its hydroxyl group ( $- O H$ ). As it donates this proton to a base, the carboxylic acid is converted into a negatively charged carboxylate ion ( $R C O O^{-}$ ).1

The ability of a carboxylic acid to donate this ion is significantly enhanced by the stability of the resulting carboxylate ion. This stability is achieved through resonance, where the negative charge is delocalized—or spread—across two equivalent oxygen atoms. Because this resonance structure lowers the energy of the resulting anion, the carboxylic acid can donate its proton more readily than other organic compounds like alcohols, which lack this stabilizing feature.13

For example, the neutralization of acetic acid by ammonia can be expressed as:
$C H_{3} C O_{2} H + N H_{3} \to C H_{3} C O_{2}^{-} + N H_{4}^{+}$ 2