A possible mechanism for hydrogenation of ethylene, in presence of mercury vapour, is `C_(2)H_(2)+ H_(2) rarr C_(2) H_(2) ("overall")` Steps : `Hg + H_(2) overset(K_1)(rarr) Hg + 2H` `H + C_(2)H_(4) overset(K_(2))(rarr) C_(2)H_(2)` `C_(2)H_(2) + H_(2) overset(K_(3))(rarr)C_(2)H_(6)+H_(-)` `H+ H overset(K_(4))(rarr) H_(2)` Determine the rate of formation of `C_(2) H_(2)` in terms of rate constants and the concentrations `[Hg], [H_(2)] and [C_(2)H_(4)]` Assume that H and `C_(2)H_(5)` reach steady state concentration.

A possible mechanism for hydrogenation of ethylene, in presence of mer

1.	A possible mechanism for hydrogenation of ethylene, in presence of mercury vapour, is `C_(2)H_(2)+ H_(2) rarr C_(2) H_(2) ("overall")` Steps : `Hg + H_(2) overset(K_1)(rarr) Hg + 2H` `H + C_(2)H_(4) overset(K_(2))(rarr) C_(2)H_(2)` `C_(2)H_(2) + H_(2) overset(K_(3))(rarr)C_(2)H_(6)+H_(-)` `H+ H overset(K_(4))(rarr) H_(2)` Determine the rate of formation of `C_(2) H_(2)` in terms of rate constants and the concentrations `[Hg], [H_(2)] and [C_(2)H_(4)]` Assume that H and `C_(2)H_(5)` reach steady state concentration.
Answer» Correct Answer - `(d[C_(2)H_(6)])/dt = k_(2) (k_(1)/k_(2) )^(1//2) [C_(2)H_(4)][Hg]^(1//2)[H_(2)]^(1//2)`