PCl5(g) ⇌ PCl3(g) Cl2(g) Calculate the value of Kc at 250°C if analysis of the mixture at equilibrium showed that [PCl3(g)] = 1.50 x 10-2 M, [Cl2(g)] = 1.50 x 10-2 M, and [PCl5(g)] = 1.18 M.