Question

Consider the following reaction:

CO(g)+2H2(g)⇌CH3OH(g)

A reaction mixture in a 5.15-L flask at a certain temperature initially contains 26.7 g CO and 2.32 g H2. At equilibrium, the flask contains 8.65 gCH3OH.

Calculate the equilibrium constant (Kc) for the reaction at this temperature.

Answer 1

                  CO(g)+2H2(g)⇌CH3OH(g)

molarity of CO   = W/G.M.Wt * volume of solution in L

                           = 26.7/28*5.15   = 0.185M

molarity of H2   = W/G.M.Wt * volume of solution in L

                        = 2.32/2*5.15   =0.225M

molarity of CH3OH = W/G.M.Wt * volume of solution in L

                                  = 8.65/32*5.15   =0.0525M

                 CO(g) +   2H2(g)⇌CH3OH(g)

        I        0.185         0.225         0

       C       -0.0525     -2*0.0525   0.0525

      E         0.1325       0.12            0.0525

        Kc = [CH3OH]/[CO][H2]^2

              = 0.0525/(0.1325)*(0.12)^2    = 27.5