5.3 Give reason why a finely divided substance is more effective as an adsorbent.

Hint: Adsorption totally depends on the surface of the adsorbate.

Adsorption is a surface phenomenon. Therefore, adsorption is directly proportional to the surface area.

A finely divided substance has a large surface area.
Both physisorption and chemisorption increase with an increase in the surface area. Hence, a finely divided substance behaves as a good adsorbent.