# What is the equilibrium constant of CH_3COOH(aq) + C_2H_5OH(aq) -> CH_3COOC_2H_5 (aq) + H_2O(l)?

${K}_{\text{eq}} = \frac{C {H}_{3} C O O {C}_{2} {H}_{5}}{\left(C {H}_{3} C O O H\right) \left({C}_{2} {H}_{5} O H\right)}$
${K}_{\text{eq"="Products"/"Reactants}}$
Reactions always find equilibrium at the least restrictive phase which in this problem, is aq. ${H}_{2} O$ is then represented as a one because it is in a liquid state. Technically you could put a one in the equation but anything times one is itself so there's no need.