How do electron-withdrawing groups change the acidity of carboxylic acids?

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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.

Electron-withdrawing groups increase the acidity of carboxylic acids by enhancing the stability of the carboxylate ion.

When a carboxylic acid donates a proton, it forms a negatively charged carboxylate ion. The stability of this resulting anion is the primary factor determining the strength of the parent acid. Electron-withdrawing groups—such as chlorine or the nitro group ( $N O_{2}$ )—exert an inductive effect by pulling electron density away from the carboxylate group. This redistribution of charge stabilizes the negative charge on the ion, making it easier for the acid to lose its proton.1

In contrast, electron-donating groups, such as the methyl group, destabilize the carboxylate ion and thereby decrease the acidity of the compound. For example, acetic acid is weaker than formic acid because the methyl group donates electrons, whereas replacing a hydrogen with a strongly electron-withdrawing atom like chlorine significantly increases acid strength.1