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How do electron-donating 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-donating groups decrease the acidity of carboxylic acids by destabilizing the carboxylate ion.

When a carboxylic acid loses a proton, it forms a negatively charged carboxylate ion. The stability of this resulting anion is a primary determinant of the parent acid's strength. Electron-donating groups (also referred to as electron-repelling groups, such as alkyl groups) increase the electron density near the carboxylate group, which destabilizes the negative charge and makes the loss of a proton less favorable.12

For example, acetic acid (CH₃COOH) is approximately 10 times weaker than formic acid (HCOOH) because the methyl group acts as an electron-donating substituent compared to the hydrogen atom in formic acid. In contrast, electron-withdrawing groups increase acidity by dispersing the negative charge and stabilizing the carboxylate ion.12