Question

Extent of adsorption of a adsorbate from aqueous solution increases with :
A) Decrease in concentration of adsorbate
B) Decrease in temperature
C) Decrease in surface area of adsorbent
D) Increase in temperature.

Answer 1

Adsorption is surface phenomenon. Adsorption is the settling or sticking of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a layer of the adsorbate on the surface of the adsorbent.

Complete answer:
Now let's examine all the options.
Option A states that the extent of adsorption of an adsorbate from aqueous solution increases with decrease with concentration of adsorbate. So this option is incorrect because Decrease in concentration of adsorbate will decrease the extent.
Option B states that the extent of adsorption of adsorbate from aqueous solution increases with decrease in temperature, this option is correct because adsorption adsorption is an exothermic process and decrease in temperature favours the adsorption.
Option number C states that the extent of adsorption of an adsorbate from aqueous solution increases with decrease in surface area of adsorbent this option is also incorrect because the surface area is directly proportional to the absorption.
Option number D says that increase in temperature extends the absorption of adsorbate, this option is also incorrect as we have seen in option number B that decrease in temperature increases the extent of absorption of absorbent.

Hence the correct answer is (B).

Note: There are two types of adsorption physical adsorption and chemical adsorption, in both types of adsorption from factors and properties are different, they are not totally different but have dissimilarities between them.