KEAM 2015 Physics and Chemistry Paper

The equilibrium constant for the equilibrium PCl5⇌PCl3(g)+Cl2(g) at a particular temperature is 2×10−2mol−2L−1. The number of moles of PCI5 that must be taken in a one-litre flask at the same temperature to obtain a concentralion of 0.20 mol of chlorine at equilibrium is