Assertion :- Lyophilic sol coagulate by adding other solvent.
Reason :- Lyophilic sol are stable due to hydration energy.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are False.

Answer

To analyze the given assertion and reason, we can break down the concepts involved in lyophilic sols and their behavior when mixed with other solvents.

### Step-by-Step Solution:

1. **Understanding Lyophilic Sols**:
- Lyophilic sols, also known as "solvent-loving" sols, are colloidal solutions that are stable and easily dispersible in a solvent, typically water. They have a strong affinity for the solvent, which contributes to their stability.

**Hint**: Remember that "lyophilic" means "loving" towards the solvent, indicating a strong interaction.

2. **Coagulation of Lyophilic Sols**:
- The assertion states that lyophilic sols coagulate when another solvent is added. This is true because adding a non-solvent or a solvent that disrupts the interactions between the sol particles and the solvent can lead to coagulation or precipitation of the sol.

**Hint**: Think about what happens when you add a substance that disrupts the balance of interactions in a colloidal solution.

3. **Hydration Energy**:
- The reason provided states that lyophilic sols are stable due to hydration energy. Hydration energy refers to the energy released when water molecules surround and stabilize sol particles. This is indeed a factor that contributes to the stability of lyophilic sols.

**Hint**: Consider how energy interactions between sol particles and solvent molecules affect stability.

4. **Evaluating the Relationship**:
- While both the assertion and reason are true, the reason does not directly explain why lyophilic sols coagulate when another solvent is added. The coagulation occurs due to the disruption of the sol's stability, which is not solely explained by hydration energy.

**Hint**: Analyze whether the reason directly supports the assertion or if it merely states a fact about the stability of lyophilic sols.

5. **Conclusion**:
- Therefore, the correct conclusion is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

### Final Answer:
- **Assertion**: True
- **Reason**: True
- **Conclusion**: Both assertion and reason are true, but the reason is not the correct explanation for the assertion.