Column - I and Column - II contains four emtries each. Entries of Column -I are to be matched with some entries of Column - II . One or more than one entries of Column -I may have the matching with the same entries of Column - II.
`{:("column-I","column-II"),((A)" Chemisorption",(P)" Exothermic"),((B)" Physical adsorption",(Q)" Endoothermic "),((C)" Desorption",(R)" Removal of adsorbed material"),((D)" Activation of adsorbent",(S)" Highly specific in nature"):}`

Answer

To solve the matching question between Column - I and Column - II, we will analyze each entry in Column - I and find the corresponding matches in Column - II based on the properties of adsorption and desorption.

### Step-by-Step Solution:

1. **Match A (Chemisorption)**:
- **Definition**: Chemisorption involves a chemical reaction between the adsorbate and the surface of the adsorbent.
- **Properties**:
- It is an **exothermic** process because energy is released when a chemical bond is formed.
- It is **highly specific** in nature due to the formation of chemical bonds.
- **Matches**:
- (P) Exothermic
- (S) Highly specific in nature

2. **Match B (Physical adsorption)**:
- **Definition**: Physical adsorption (physisorption) involves weak van der Waals forces and does not involve a chemical reaction.
- **Properties**:
- It is also **exothermic**, as energy is released when the adsorbate is attracted to the surface.
- **Matches**:
- (P) Exothermic

3. **Match C (Desorption)**:
- **Definition**: Desorption is the process of removing adsorbed material from the surface of the adsorbent.
- **Properties**:
- It is an **endothermic** process because energy is required to overcome the forces holding the adsorbate to the surface.
- It involves the **removal of adsorbed material**.
- **Matches**:
- (Q) Endothermic
- (R) Removal of adsorbed material

4. **Match D (Activation of adsorbent)**:
- **Definition**: Activation of adsorbent refers to increasing the adsorbing power of the adsorbent, often by increasing the surface area or roughness.
- **Properties**:
- This process can be considered **endothermic** as it may require energy input to increase the surface area.
- **Matches**:
- (Q) Endothermic

### Final Matches:
- A → P, S
- B → P
- C → Q, R
- D → Q

### Summary of Matches:
- A (Chemisorption) → P (Exothermic), S (Highly specific in nature)
- B (Physical adsorption) → P (Exothermic)
- C (Desorption) → Q (Endothermic), R (Removal of adsorbed material)
- D (Activation of adsorbent) → Q (Endothermic)