Distinction between Adsorption and Absorption
Sorption
It is a process in which both adsorption and absorption take place simultaneously, the term sorption is simply used.
Positive and Negative Adsorption
When the concentration of the adsorbate is more on the surface of the adsorbent than in the bulk, it is called positive adsorption.
On the other hand, if the concentration of the adsorbate is less relative to its concentration in the bulk, it is called negative adsorption, e. g., when a dilute solution of KCl is shaken with blood charcoal, it shows negative adsorption.
Distinction between Physisorption and Chemisorption