Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas:...

Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas: . A gas vessel is charged with a mixture of which is allowed to equilibrate at 450 K. At equilibrium the partial pressures of the three gases are and (a) What is the value of at this temperature? (b) Does the equilibrium favor reactants or products?