What is the equilibrium constant, Kp, of this reaction?

Question

Phosgene (carbonyl chloride), COCl2, is an extremely toxic gas that is used in manufacturing certain dyes and plastics. Phosgene can be produced by reacting carbon monoxide and chlorine gas at high temperatures:

CO(g)+Cl2(g)⇌COCl2(g)

Carbon monoxide and chlorine gas are allowed to react in a sealed vessel at 450 ∘C . At equilibrium, the concentrations were measured and the following results obtained:

Gas Partial Pressure(atm)

CO 0.800

Cl2 1.25

COCl2 0.280

What is the equilibrium constant, Kp, of this reaction?

Answer 1

CO(g) + Cl₂(g) ⇌ COCl₂(g)

Kp = (P_COCl2) / (P_CO) / (P_Cl2) = 0.280 atm /(0.800 atm)(1.25 atm)

Kp = 0.28