Equations for Chemisorption Isotherms

The activation energy for the chemisorption of nitrogen on an iron catalyst, as measured by Zwietering and Roukens (360) (hence the curve of Fig. 36 just mentioned), can be represented by the expression 

The rate of chemisorption at a pressure of 20 cm. mercury could be represented by 

The entropy term partly counteracts the term containing the activation energy. Restricting ourselves to one temperature, we can write the equation as 

The constant fcj in this equation contains that part of the equation for 

Equation (68) has the same form as an empirical expression found by Zeldowitsch (364) in 1934 viz., 

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