Adsorption is surface phenomenon, while absorption concerns with the whole mass of the absorbent.
In adsorption, the substance is only retained on the surface and does not go into the bulk or interior of the solid or liquid. Absorption implies that substance is uniformly distributed throughout the body of the solid or liquid.
In adsorption, the concentration of the adsorbed molecules is always greater in the immediate vicinity of the surface tlian in the free phase. Absorption involves bulk penetration of the molecules into the structure of the solid or liquid by some process of diffusion.
Adsorption is a rapid process and equilibrium is attained in a short time. In absorption the equilibrium takes place slowly.
Such substance is said to be sorbed and the phenomenon is known as sorption.
What is phenomenon of adsorption.