Langmuir adsorption model

The Langmuir adsorption model explains adsorption by assuming an adsorbate behaves as an ideal gas at isothermal conditions. At these conditions the adsorbate's partial pressure, ${\displaystyle p_{A}}$, is related to the volume of it, ${\displaystyle V}$, adsorbed onto a solid adsorbent. The adsorbent, as indicated in Figure 1, is assumed to be an ideal solid surface composed of series of distinct sites capable of binding the adsorbate. The adsorbate binding is treated as a chemical reaction between the adsorbate molecule ${\displaystyle A_{g}}$ and an empty site, ${\displaystyle S}$. This reaction yields an adsorbed complex ${\displaystyle A_{ad}}$ with an associated equilibrium constant ${\displaystyle K_{eq}}$

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