For the equilibrium PCl5(g) PCl3(g) + Cl2(g), Kc = 2.0 × 10…

For the equilibrium PCl5(g) PCl3(g) + Cl2(g), Kc = 2.0 × 101 at 240°C. If pure PCl5 is placed in a 1.00-L container and allowed to come to equilibrium, and the equilibrium concentration of PCl3(g) is 0.50 M, what is the equilibrium concentration of PCl5(g)?