Consider the following reversible reaction.
2H2O(g) + 2H2(9)+O2(g)

Answer:
Keq = [H2]^2[O2]
Explanation:
Keq = ([H2]^2[O2])/[H2O], but as long as [H2O] in a chemical eq is considered 1, the final Keq = [H2]^2[O2]