Ethanoic acid more closely resembles alcohols, or hydroxyl compounds, in its reactions.

This is because the -OH group in ethanoic acid is able to donate a proton (H+), which is characteristic of alcohols. In contrast, the carbonyl group in ethanoic acid is not able to donate a proton.

For example, when ethanoic acid reacts with a base, such as sodium hydroxide, it forms a salt and water. This is a typical reaction of alcohols.

CH3COOH + NaOH → CH3COONa + H2O

In contrast, when ethanoic acid reacts with a carbonyl compound, such as formaldehyde, it forms a hemiacetal. This is a typical reaction of alcohols with aldehydes or ketones.

CH3COOH + HCHO → CH3CH(OH)2