Is the Surface Reaction Rate-Limiting

2 Is the Suriace Reaction Rate-Limiting The rate of surface reaction is 

Since we cannot readily measure the concentrations of the ad.sorbed species, we must utilize the adsorption and desorption steps to eliminate Cc-s and Cb-s from this equation. 

From the adsorption rate expression in Equation (10-25) and the condition that and ko are very large by comparison with when surface reaction is limiting (i.e., = 0), we obtain a relationship for the sur- 

In a similar manner, the surface concentration of adsorbed benzene can be evaluated from the desorpdcHt rate expression (Equation (10-29)] together with the approximation  

For desorption-limited reactions, both ad an4 are very large compared with which is small 

From the rate expression for surface reaction, Equation (10-26), we set 

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Is the Surface Reaction Rate-Limiting 677 Is the Desorption of Benzene Rate-Limiting 678... 

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