PCl5 , PCl3 and Cl2 are at equilibrium at 500 K in a closed container and their concentrations are 0.8\times 10^{-3}\; mol\; L^{-1} , 1.2 \times 10^{-3} mol L^{-1} and 1.2 \times 10^{-3} mol L^{-1} respectively.
, and are at equilibrium at 500 K in a closed container and their concentrations are , and respectively. The value of for the reaction PCl5 (g) PCl3 (g) + Cl2 (g) will be