Chemistry - Chemical Equilibrium Question with Solution | TestHub

On addition of inert gas at constant P \& T, reaction moves in the direction of greater no. of moles so it will shift in forward direction, so $\left[{\mathrm{PCl}}_5\right]$ decrease and $\left[{\mathrm{PCl}}_3\right]\&\left[{\mathrm{Cl}}_2\right]$ will increase.