Local and Global r vs Dependence

In view of the previous section and of Figs. 4.28 to 4.33 one may conclude the following  

When examining the r vs d behaviour of a catalytic system at a local level, 

When examining the r vs O behaviour at a global level, i.e. over the entire experimentally accessible O range (typically over 1.5 to 2eV) then there are four types of behaviour (Fig. 4.34b). 

It is a recent discovery, presented in Chapter 6, that behind the apparent chaos of Table 4.2 there are some simple regularities which enable one to predict the r vs X local and global behaviour on the basis of the open-circuit 

Thus in Table 4.3 we add to Table 4.2 the last, but quite important, available piece of information, i.e. the observed kinetic order (positive order, negative order or zero order) of the catalytic reaction with respect to the electron donor (D) and the electron acceptor (A) reactant. We then invite the reader to share with us the joy of discovering the rules of electrochemical promotion (and as we will see in Chapter 6 the rules of promotion in general), i.e. the rules which enable one to predict the global r vs O dependence (purely electrophobic, purely electrophilic, volcano, inverted volcano) or the basis of the r vs pA and r vs pD dependencies. 

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