\( \mathrm{PCl}_{5}, \mathrm{PCl}_{3} \) and \( \mathrm{Cl}_{2} \) are at equilibrium at \( 500 \mathrm{~K} \) in a clos…

\( \mathrm{PCl}_{5}, \mathrm{PCl}_{3} \) and \( \mathrm{Cl}_{2} \) are at equilibrium at \( 500 \mathrm{~K} \) in a closed container and their concentrations are \( 0.8 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1}, 1.2 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1} \) and \( 1.2 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1} \) respectively. The value of \( K_{c} \) for the reaction \( \mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g}) \) will be