# Acetic acid has 2 carbon, 4 hydrogen, and 2 oxygen atoms per molecule. What is the empirical formula for acetic acid?

Given the defintion, the empirical formula of ${H}_{3} C - C {O}_{2} H , {C}_{2} {H}_{4} {O}_{2}$, $=$ $C {H}_{2} O$. The molecular formula, as it is here, is always a multiple of the empirical formula.