Question

Calculate the equilibrium constant, Kc, at 298 K for the reaction 2 SO2(g) + O2(g) ⇌ 2 SO3(g) when the initial concentrations of SO2, O2, and SO3 are 0.100 M, 0.200 M, and 0.300 M, respectively.

Answer 1

To calculate the equilibrium constant, Kc, we need to first find the equilibrium concentrations of all the species involved in the reaction. We can do this by setting up an ICE  Initial, Change, Equilibrium  table.For the reaction: 2 SO2 g  + O2 g   2 SO3 g Initial concentrations:[SO2] = 0.100 M[O2] = 0.200 M[SO3] = 0.300 MLet x be the change in concentration at equilibrium:Change in concentrations:[SO2] = -2x[O2] = -x[SO3] = +2xEquilibrium concentrations:[SO2] = 0.100 - 2x[O2] = 0.200 - x[SO3] = 0.300 + 2xNow, we can write the expression for Kc:Kc = [SO3]^2 /  [SO2]^2 * [O2] At equilibrium, we can substitute the equilibrium concentrations into the Kc expression:Kc = [ 0.300 + 2x ^2] /  [ 0.100 - 2x ^2] *  0.200 - x  To find the value of Kc, we need to know the value of x. However, we cannot solve for x without knowing the value of Kc. Since we are not given the value of Kc, we cannot calculate the exact equilibrium concentrations or the value of Kc for this reaction at 298 K.