The adsorption of aniline, phenol, and toluene on low surface area silica has been studied with temperature-programmed desorption (TPD) and laser desorption methods. These adsorption systems can serve as models for studying the mechanism of laser-induced thermal desorption, where heating rates and desorption rates are orders of magnitude larger than in TPD. For this purpose, results obtained at low heating rates need to be extrapolated to the regime of very high laser heating rates. This extrapolation relies on a model of the adsorbate-surface interaction that involves a distribution of binding sites. Calculations based on this model match experimental measurements on the depletion of adsorbed layers subjected to laser-induced desorption. The interaction energy of aniline and phenol was found to depend on the hydration of the surface, demonstrating the role of hydrogen bonding with silanol sites.