17 The equilibrium constant Kc for the reaction below is 000

17. The equilibrium constant Kc for the reaction below is 0.00356 at a certain temperature. Br2(g) 2Br(g) If the initial concentrations are [Br2] = 0.0580 M and [Br] = 0.0360 M, calculate the concentrations of these species at equilibrium. [Br2] = M [Br] = M 18. H2(g) + CO2(g) H2O(g) + CO(g) at 700°C, Kc = 0.534. Calculate the number of moles of H2 that are present at equilibrium if a mixture of 0.800 mole of CO and 0.800 mole of H2O is heated to 700°C in a 30.0L container. mol

Solution

                    Br2(g)    2Br(g)

I                     0.058          0.036

C                   +x               -2x

E                0.058+x         0.036-2x

        Kc    = [Br]^2/[Br2]

     0.00356    = (0.036-2x)^2/(0.058+x)

    0.00356*(0.058+x) = (0.036-2x)^2

        x   = 0.01

   [Br]   = 0.036-2x   = 0.036-2*0.01   = 0.016M

   [Br2]   = 0.058+x   = 0.058+0.01   = 0.068M

                         H2(g) + CO2(g) H2O(g) + CO(g)

I                          0          0                 0.8       0.8

C                       +x          +x                 -x        -x

E                       +x          +x                0.8-x    0.8-x

             kc    = [H2O][CO]/[H2][CO2]

            0.534   = (0.8-x)(0.8-x)/x*x

          0.534x^2 = (0.8-x)^2

          x   = 0.462

        no of moles of H2 = x   = 0.462moles