Heats of Adsorption Different Substances on Solid Surfaces

3 Heats of Adsorption (Different Substances) on Solid Surfaces 

The quantity qimm is measured from calorimetry where temperature change is measured after a solid (in a finely divided state) is immersed in a given liquid. Since these measurements can be carried out with microcalorimeter sensitivity, there is much systematic data in the literature on this subject. When a polar solid surface is immersed in a polar liquid, it can be expected that there will be a larger qimm than if the liquid was an alkane (nonpolar). The values of some typical systems is depicted in Table 5.5. 

These data further show that such studies are sensitive to the surface purity of solids. For example, if the surface of glass powder is contaminated with nonpolar gas, then its qimm value will be lower than that in the case of pure glass. 

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