Question

A sample of pure PCl₅ was introduced into an evacuated vessel at 473 K. After equilibrium was attained, concentration of PCl₅ was found to be 0.5 × 10^–1 mol L^–1. If value of Kc is 8.3 × 10^–3, what are the concentrations of PCl₃ and Cl₂ at equilibrium? 

Answer 1

Let the concentrations of both PCl₃ and Cl₂ at equilibrium be x molL^–1. The given reaction is: 

Now we can write the expression for equilibrium as: