Assertion (A): Caesium metal when dissolved in liquid amtmonia forms a blue-coloured solution.
Reason(R ): The blue solution is a good conductor of electricity.

Options

A. If both (A) and (R ) are correct and (R ) is the correct explanation of (A).
B. If both (A) and (R ) are correct, but (R ) is not the correct explanation of (A).
C. If (A) is correct, but (R ) is incorrect.
D. If (A) is incorrect, but (R ) is correct.

Explanation

To analyze the given assertion and reason, we can break it down into steps:

### Step 1: Understanding the Assertion
The assertion states that "Caesium metal when dissolved in liquid ammonia forms a blue-coloured solution." This is indeed true. Alkali metals, including caesium, can dissolve in liquid ammonia, resulting in a characteristic blue solution.

**Hint:** Remember that alkali metals have unique properties when interacting with solvents like ammonia.

### Step 2: Understanding the Reason
The reason provided is that "The blue solution is a good conductor of electricity." This is also true. The blue solution contains solvated electrons, which are free to move and carry charge, making the solution a good conductor of electricity.

**Hint:** Focus on the role of solvated electrons in conducting electricity in solutions.

### Step 3: Analyzing the Relationship
While both the assertion and reason are correct, we need to determine if the reason correctly explains the assertion. The blue color of the solution is due to the absorption of light in the red region of the spectrum by the solvated electrons, which then emit blue light. The reason provided does not explain why the solution is blue; it only states that the solution conducts electricity.

**Hint:** Consider whether the reason directly addresses the cause of the assertion's claim.

### Step 4: Conclusion
Since both the assertion and reason are correct but the reason does not adequately explain the assertion, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

**Final Answer:** Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.