Mass transfer and electron-exchange processes

1 Mass transfer and electron-exchange processes In considering electron-exchange reactions at electrodes we are concerned essentially with the layer of solution very close to the electrode surface. It must be borne in mind, however, that an oxidant or reductant in solution has to have some means of reaching the electrode vicinity. There are a number of ways in which this can occur and these are included under the general heading of mass transfer processes. They are  

Considerable variation in the relative rates of mass transfer and electron-exchange processes is possible. The simplest interpretation of electrochemical reactions assumes that the rates of all processes are virtually infinite. 

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