The effect of temperature on the adsorption of gas molecules on a solid surface can be explained using adsorption isotherms, such as the Langmuir and Freundlich isotherms. Generally, the adsorption process can be either exothermic or endothermic, depending on the nature of the adsorbate-adsorbent interaction.In most cases, the adsorption process is exothermic. This means that the process releases heat as the gas molecules are adsorbed onto the solid surface. The reason for this is that the adsorption process involves the formation of chemical bonds or van der Waals forces between the gas molecules and the solid surface, which releases energy in the form of heat.As the temperature increases, the adsorption capacity of the solid surface typically decreases. This is because the increased thermal energy of the gas molecules can overcome the attractive forces between the gas molecules and the solid surface, leading to desorption. This effect can be described by the van 't Hoff equation:ln K = -H/RT + ln A where K is the equilibrium constant, H is the enthalpy change of the adsorption process, R is the gas constant, T is the temperature, and A is a constant.Experimental data supporting the exothermic nature of adsorption can be obtained by measuring the adsorption capacity of a solid surface at different temperatures. For example, the adsorption of nitrogen gas onto activated carbon has been found to decrease with increasing temperature, which is consistent with an exothermic process.In some cases, the adsorption process can be endothermic, meaning that it absorbs heat. This is less common and typically occurs when the adsorption process involves breaking of strong bonds in the adsorbate or adsorbent, which requires an input of energy. An example of an endothermic adsorption process is the adsorption of hydrogen gas onto certain metal surfaces.In conclusion, the effect of temperature on the adsorption of gas molecules on a solid surface depends on the nature of the adsorbate-adsorbent interaction. In most cases, the adsorption process is exothermic, and the adsorption capacity decreases with increasing temperature. This can be supported by experimental data and described by the van 't Hoff equation.