$PC{\mathcal{l}}_5\rightleftharpoons PC{\mathcal{l}}_3+C{l}_2$
If the equilibrium constant $\left(K_c\right)$  for the above reaction at 500 K is 1.79 and the equilibrium concentration of  $PC{\mathcal{l}}_5$ and  $PC{\mathcal{l}}_3$  are $1.41M$  and $1.59M$  respectively. Then the concentration of  $C{\mathcal{l}}_2$  is approximately