A system initially contains 0.100 mol each of the three species sealed in a 10.0 L container. The temp was raised to a temp where the equilibrium constant Kc, is 12.6 for
PCl3(g) + Cl2(g)--> <-- PCl5(g)
Calculate the equilibrium concentration of all species.
M = mols/L = 0.1 mol/10L = 0.01M
Qc = (PCl5)/(PCl3)(Cl2) = 0.01/0.01*0.01 = 100. Since Qc>Kc that means the means too much product and too small reactant so the reaction will move to the left to achieve equilibrium.
..........PCl3(g) + Cl2(g) <==> PCl5(g)
I.........0.01.....0.01............0.01
C..........+x.......+x.............-x
E.......0.01+x....0.01+x.........0.01-x
Substitute the E line into Kc expresion and solve for x, then evaluate 0.01+x and 0.01-x.