Phosphorus Pentachloride Decomposes to Phosphorus Trichloride at High Temperatures According

Phosphorus pentachloride decomposes to phosphorus trichloride at high temperatures according to the equation: PCl₅(g) ⇌ PCl₃(g) + Cl₂(g)
At 250° 0.125 mol L^-1 PCl₅ is added to the flask. If K_c = 1.80 mol L^-1, what are the equilibrium concentrations of each gas?

A) [PCl₅] = 0.00765 mol L^-1, [PCl₃] = 0.117 mol L^-1, and [Cl₂] = 0.117 mol L^-1
B) [PCl₅] = 0.0625 mol L^-1, [PCl₃] = 0.335 mol L^-1, and [Cl₂] = 0.335 mol L^-1
C) [PCl₅] = 1.80 mol L^-1, [PCl₃] = 1.80 mol L^-1, and [Cl₂] = 1.80 mol L^-1
D) [PCl₅] = 3.96 mol L^-1, [PCl₃] = 3.83 mol L^-1, and [Cl₂] = 3.83 mol L^-1