Question

A poisonous gas is adsorbed at activated charcoal. The activated charcoal is:
(A) Absorber
(B) Adsorbate
(C) Adsorbent
(D) Absorbate

Answer 1

Hint: Adsorption is a surface phenomenon. The solids that have porous surface or have large surface area can act as a good adsorbents for specific material and they are often regarded as good adsorbents.

Complete step by step solution:
We know that surface phenomena that occur at the surfaces are called surface chemistry.
- The accumulation of the species on the surface of substance rather than the bulk of the substance is called adsorption.
- The molecular species or substance that accumulates in the surface is called adsorbate.
- In adsorption, the material on the surface of which adsorption takes place is called adsorbent.
- We are given that a poisonous gas gets adsorbed by activated charcoal. So, here the gas gets accumulated on activated charcoal. So, we can say that the poisonous gas is adsorbate. The activated charcoal as adsorbent.
- Solids that are in a finely divided state have larger surface area and they can act as good adsorbers.
e.g. Silica gel, clay, charcoal, metals in finely divided state
- The process of removal of adsorbed substance from the surface is called desorption.
 - Adsorption can be divided into mainly two types; physisorption and chemisorption.
- Thus, we can conclude here that the gas which is adsorbed on activated charcoal is called adsorbate.

Therefore, the correct answer to this question is (B).

Note: In adsorption, the substance is concentrated on the surface only and in absorption, the substance gets uniformly distributed through the bulk of the material. We can use the term sorption to describe both the processes.