In physiosorption, or physical adsorption, molecules of pollutants will be attached to the surfaces of soil grains by Van der Waal forces, which are known to be weak long range forces. The amounts of energies involved in such attachments are normally of low magnitudes and are not sufficient for bond breaking. Thus, pollutant molecules sticking to the soil surface will retain their chemical identities, although they might be stretched or bent on account of their proximity to the surface.