In physical adsorption, the molecules of adsorbate are held by chemical forces. True or False

Answer

To determine whether the statement "In physical adsorption, the molecules of adsorbate are held by chemical forces" is true or false, we can analyze the concepts of physical adsorption and chemisorption.

### Step-by-Step Solution:

1. **Understanding Adsorption**:
- Adsorption is the process where molecules (adsorbate) adhere to the surface of a solid or liquid (adsorbent).

2. **Types of Adsorption**:
- There are two main types of adsorption: physical adsorption (physisorption) and chemical adsorption (chemisorption).

3. **Physical Adsorption (Physisorption)**:
- In physical adsorption, the adsorbate molecules are held to the adsorbent surface by weak forces. These forces are primarily van der Waals forces, which are much weaker than chemical bonds.
- Physisorption is characterized by its reversibility, meaning that the adsorbate can easily be removed from the adsorbent.

4. **Chemical Adsorption (Chemisorption)**:
- In contrast, chemisorption involves the formation of strong chemical bonds between the adsorbate and the adsorbent. This type of adsorption is typically irreversible because breaking these chemical bonds requires significant energy.

5. **Analyzing the Statement**:
- The statement claims that in physical adsorption, the molecules of adsorbate are held by chemical forces. Since we established that physical adsorption involves weak van der Waals forces and not chemical bonds, the statement is incorrect.

6. **Conclusion**:
- Therefore, the answer to the question is **False**.