What Happens When One Rate-Determining Step Is Not Dominant

2 What Happens When One Rate-Determining Step Is Not Dominant  

The way we have been writing our account so far, one reaction in a sequence controls the rate of the whole reaction. But this is an idealization and a much more general reaction, which at first does not speak of an r.d.s., is as follows [5]  

Here fe1 k2, and k3 are the rate constants of consecutive steps 1,2,3, One sees at once that if, say, 

However, one has to admit that, sometimes, k, = kj and both are much less than k3. Then, from the electrocatalysis point of view, there will be a half way house, the structure of a good catalyst will have to be chosen with the properties of both i and j taken into account. 

This is easy if k2 and k3 need the same surface to increase the rate of each step. But there are ways of meeting the situation even if (as one might say) there are two nearly equal r.d.s. s. Could an electrode surface be made with tiny patches of metals favoring k2 but also of metals favoring k  

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