Absorption

Adsorption

The phenomenon of assimilation in which the constituent of a substance enters into the bulk phase of another substance.

The phenomenon in which the adhesion of constituents of a substance takes place on the surface of another substance.

Bulk phenomenon

Surface phenomenon

Uniform distribution of absorbate

Adsorbate concentrates only on the surface

Endothermic process

Exothermic process

Independent of temperature

Temperature-dependent

The rate of reaction is uniform for absorption

The rate of reaction increases slowly and then achieves equilibrium.

Example- absorption of liquid by a sponge.

Example- adsorption of pollutants by pollution masks.