The equilibrium composition for the reaction $\mathrm{PCl}_3+\mathrm{Cl}_2 \rightleftharpoons \mathrm{PCl}_5$ at 298 K is given below:
$$ \begin{aligned} & {\left[\mathrm{PCl}_3\right]_{\mathrm{leq}}=0.2 \mathrm{~mol} \mathrm{~L}^{-1}} \\ & {\left[\mathrm{Cl}_2\right]_{\mathrm{eq}}=0.1 \mathrm{~mol} \mathrm{~L}^{-1},} \\ & {\left[\mathrm{PCl}_5\right]_{\mathrm{leq}}=0.40 \mathrm{~mol} \mathrm{~L}^{-1}} \end{aligned} $$
If 0.2 mol of $\mathrm{Cl}_2$ is added at the same temperature, the equilibrium concentrations of $\mathrm{PCl}_5$ is $\_\_\_\_$ $\times 10^{-2} \mathrm{~mol} \mathrm{~L}^{-1}$. (Given: $\mathrm{K}_{\mathrm{c}}$, for the reaction at 298 K is 20 )