Assertion: Anhydrous `AlCl_(3)` is covalent while hydrated `AlCl_(3)` is ionic.
Reason: In water `AlCl_(3)` is presennt as `Al_((aq.))^(3+) and Cl_((aq.))^(-)` ion.

Options

A. If both (A) and (R) are true and (R) is the correct explanation of (A)
B. if both (A) and (R) are true but (R) is not correct explanation of (A)
C. If (A) is true but (R) is false
D. If (A) is false but (R) is false

Answer

To solve the question, we need to analyze both the assertion and the reason provided and determine their correctness.

### Step-by-Step Solution:

**Step 1: Analyze the Assertion**
- The assertion states that anhydrous \( \text{AlCl}_3 \) is covalent while hydrated \( \text{AlCl}_3 \) is ionic.
- **Explanation**: Anhydrous \( \text{AlCl}_3 \) consists of aluminum and chlorine atoms that are bonded covalently. In the solid state, it forms a polymeric structure where the bonds between aluminum and chlorine are covalent. When \( \text{AlCl}_3 \) is hydrated, it interacts with water molecules, leading to the formation of ions.

**Step 2: Analyze the Reason**
- The reason states that in water, \( \text{AlCl}_3 \) is present as \( \text{Al}^{3+} \) and \( \text{Cl}^- \) ions.
- **Explanation**: When \( \text{AlCl}_3 \) is dissolved in water, it undergoes hydrolysis and dissociates into \( \text{Al}^{3+} \) ions and \( \text{Cl}^- \) ions. This process indicates that the hydrated form of \( \text{AlCl}_3 \) behaves ionically in solution.

**Step 3: Determine the Correctness of Assertion and Reason**
- Both the assertion and the reason are correct statements.
- However, the reason does not correctly explain why the assertion is true. The assertion is about the nature of bonding in anhydrous vs. hydrated \( \text{AlCl}_3 \), while the reason focuses on the ionic dissociation in water, which is a consequence of hydration rather than a direct explanation of the bonding nature.

**Conclusion**
- The assertion is true, and the reason is also true, but the reason is not the correct explanation of the assertion.

### Final Answer:
- Option 2: Assertion and reason are true, but the reason is not the correct explanation of the assertion.