Single electrode reaction with more than one electron transfer

Single electrode reaction with more than one electron transfer 

The first step in dealing with more complex reactions is to define the relation between current and flux to accommodate more than one electron. Diffusion effects and the fluxes remain as treated above. For example, for two electrons 

This is consistent, at equilibrium, with the Nemst equation for the two-electron reaction and requires that 

The consequences of treating the overall reaction as two consecutive steps 

It is also possible to separate multielectron reactions into slightly more complicated separate one-electron steps. The common gas evolving, electro-catalytic, reactions are of this type. However, this is only useful if the intermediate one-products are stable and show a definite presence in the electrochemical kinetics. As an example, consider the consequence of splitting eqn. (38) into its component one-electron steps 

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