The combustion of acetic acid, also known as ethanoic acid, can be represented by the following balanced chemical equation:

CH3COOH + 2O2 → 2CO2 + 2H2O

In this reaction, one molecule of acetic acid (CH3COOH) reacts with two molecules of oxygen (O2) to produce two molecules of carbon dioxide (CO2) and two molecules of water (H2O).