Which term from the following is not related to adsorption ?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Effluent
Adsorption is the accumulation of molecules at the surface of a substance rather than in its bulk. Its terms are:
Adsorbent: the substance on whose surface adsorption takes place (charcoal, silica gel).
Adsorbate: the substance that is adsorbed on the surface.
Desorption: the process of removing an adsorbed substance from the surface.
Effluent is a liquid waste, such as sewage or industrial waste water discharged into a river; it is not a term of adsorption.
Option (1) Adsorbent — Related to adsorption. It is the surface that holds the adsorbate.
Option (2) Effluent — Not related to adsorption. It is liquid waste.
Option (3) Adsorbate — Related to adsorption. It is the substance held on the surface.
Option (4) Desorption — Related to adsorption. It is the reverse of adsorption.
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic is not there in the latest NCERT book (2026-27), and it is also out of the CUET 2026 syllabus.
NCERT (Pre-rationalised edition, 2022-23):
Adsorption – …
NCERT (Pre-rationalised edition, 2022-23):
Adsorption – …
