Reaction Mechanisms Involving a Stoichiometric Number Greater than

Reaction Mechanisms Involving a Stoichiometric Number Greater than 1 

In the closed reaction sequences considered in this work, stoichiometric numbers greater than 1 can arise only in order to satisfy a material balance for a reaction step preceding or following the rds that creates or consumes V intermediates in a single transition state. 

If it is assumed that the rate of the overall reaction is controlled by the transition state of the rds, then the net rate expression will be 

The potential-dependent exponential term is also independent of v. This may be explained if we recall that the effect of an applied overpotential in electrochemical kinetics is to modify the relative energies of reactant and product curves through a change in the Fermi level energy and, by extension, that of the transition state for the elanentary (recall footnote h) reaction step. The potential dependence of the energy of the transition state is sensitive to the number of electrons transferred in it, but not the v times that it must occur per turnover of the overall reaction thus the exponential in Eq. (52) is independent of v. 

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