Rate when adsorptive equilibrium is maintained

In such cases, the overall rate equals the rate of the surface reaction and the surface reaction rate is said to be controlling. The stoichiometric equation is 

When both A and B are in adsorptive equilibrium, but the reaction is between adsorbed A and gas phase B, the stoichiometric and rate equations are her + B Products 

In such cases one or more of the participants are not in adsorptive equilibrium and the overall rate is determined by the adsorption rates. Usually only one of the participants is assumed not to be in adsorptive 

Other equations with chemical reaction equilibrium on the surface are summarized in Table 6.2. 

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