Assertion `(A)`: Temporary hardness in water is due to the presence of chlorides of magnesium.
Reason `(R)` :Temporary hardness is removed by Clark's method.

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 statements, we will break down the assertion and reason step by step.

### Step 1: Understand the Assertion
The assertion states: "Temporary hardness in water is due to the presence of chlorides of magnesium."

- **Evaluation**: This statement is incorrect. Temporary hardness in water is primarily caused by the presence of bicarbonates of calcium (Ca(HCO₃)₂) and magnesium (Mg(HCO₃)₂), not chlorides. Chlorides do not contribute to temporary hardness.

### Step 2: Understand the Reason
The reason states: "Temporary hardness is removed by Clark's method."

- **Evaluation**: This statement is correct. Clark's method involves the addition of lime (calcium hydroxide, Ca(OH)₂) to the water, which reacts with the bicarbonates to form insoluble precipitates, thereby removing the temporary hardness.

### Step 3: Conclusion
Now, we can conclude the relationship between the assertion and reason:

- The assertion (A) is **incorrect**.
- The reason (R) is **correct**.

Since the assertion is false and the reason is true, the correct answer to the question is that the assertion is incorrect while the reason is correct.

### Final Answer:
- Assertion (A) is incorrect.
- Reason (R) is correct.
- Therefore, the correct option is that the assertion is false and the reason is true.

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