Question

Which of the following is not the application of adsorption?
(A) De-ionisation of water
(B) Gas masks
(C) Hygroscopic mixture of \[CaC{l_2}\]
(D) Heterogeneous catalysis

Answer 1

Hint: Try to recall that adsorption is the phenomenon of attracting and retaining molecules of substance at the surface of solid or liquid resulting in higher concentration of molecules on the surface than in the bulk. Now, by using this you can easily find the correct option from the given ones.

Complete step by step solution:
It is known to you that adsorption is the phenomenon of higher concentration of particles of gas or liquid on the surface than in the bulk of the solid. Some of the important applications of adsorption are as follows:
In gas masks: Activated charcoal or a mixture of adsorbents is generally used in gas masks to adsorb poisonous and toxic gases from air. These masks are commonly used by the miners because there are poisonous gases in the atmosphere of coal mines.
Hygroscopic mixtures of \[CaC{l_2}\]: \[CaC{l_2}\] are commonly used to absorb humidity or moisture from air. This is necessary for storage of delicate instruments which might otherwise be damaged by moisture.
Heterogeneous catalysis: The phenomenon of adsorption is useful in the heterogeneous catalysis. Adsorption of reactants on the solid surface of catalysts increases the rate of reaction.

Therefore, from above we can conclude that option A is the correct option to the given question.

Note:
It should be remembered to you that due to the difference in degree of adsorption of gases by charcoal, a mixture of noble gases can be separated by adsorption on coconut charcoal at different temperatures.
Also, you should remember that a number of drugs are used to kill the germs by getting adsorbed on them.