Question

What will be the effect of increase in temperature on physical adsorption?
A. It will decrease
B. It will increase
C. First increase then decrease
D. None of these

Answer 1

Hint: To answer this question we have to know about physical adsorption. Physical adsorption takes place between the adsorbate and adsorbent due to physical bonding. Physical adsorption has weak vanderwaal’s force or hydrogen bonding.

Complete Step by Step Solution:
In the method of physical adsorption, the adsorption takes place between the adsorbate and adsorbent due to weak hydrogen bonding or van der waals force.
Physical adsorption is inversely proportional to temperature. It increases with decrease in temperature because as the temperature increases the bond vibration increases so, the adsorption decreases.
Thus the correct option is A.

Additional Information:
The properties of physical adsorption are as follows-
1. It has weak forces like vander waals force or hydrogen bonding between adsorbate and adsorbent.
 2. Physical adsorption is reversible in nature.
3. Physical adsorption depends on the surface area of the adsorbent because as the surface area of the adsorbent will increase, physical adsorption additionally will increase.
4. Physical adsorption is the slowest process.
5. It is not independent of temperature. It increases with a decrease in temperature.
6. It is highly specific.
7. It is spontaneous and has negative enthalpy and entropy.

Note: The process of holding gas, liquid or solid molecules on solid is called as adsorption. There are two types of adsorption present. One of this is physical adsorption and another one is chemical adsorption.