The Langmuir Adsorption Analogy

The adsorption of gas molecules occurs at discrete sites on the surface. 

The energy of adsorption on the surface is independent of the presence of other adsorbed molecules. 

The maximum amount of adsorption corresponds to one molecule per site. 

The adsorption is localized and occurs by collision of gas phase molecules with vacant sites. 

The desorption rate depends only on the amount of adsorbed material on the surface. 

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