The formation of phosgene is represented as,  ${\text{CO}}_{\left(\text{g}\right)}+{\text{Cl}}_{\text{2\hspace{0.17em}}\left(\text{g}\right)}\rightleftharpoons {\text{COCl}}_{\text{2}\left(\text{g}\right)}$. The reaction is carried out in 500mL flask. At equilibrium 0.3 mole of phosgene, 0.1 mole of CO and 0.1 mole of ${\text{Cl}}_{\text{2}}$  are present. The equilibrium constant of the reaction is