At 250ºC,the Equilibrium Constant,K_P,for the Reaction PCl⁵(g) PCl₃(g)+ Cl₂(g)is

At 250ºC,the equilibrium constant,K_P,for the reaction PCl⁵(g) PCl₃(g) + Cl₂(g) is 1.80. Sufficient PCl₅ is put into a reaction vessel to give an initial pressure of 2.74 atm at 250ºC.What is the partial pressure of PCl₅ after the system has reached equilibrium.

A) 1.50 atm
B) 1.24 atm
C) 4.24 atm
D) 0.94 atm
E) 1.12 atm