In the following question, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.
Assertion (A): Coagulation power of `Al^(3+)` is more than `Na^(+)`.
Reason (R): Greater the valency of the flocculating ion added, greater is its power to cause precipitation (Hardy-Schulze rule).

Options

A. Both A and Rare true and R is the correct explanation of A
B. Both A and R are true but explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

To solve the question, we need to analyze both the Assertion (A) and the Reason (R) provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the coagulation power of \( \text{Al}^{3+} \) is more than \( \text{Na}^{+} \).
- Coagulation power refers to the ability of an ion to destabilize a colloidal solution and cause precipitation.

2. **Analyzing the Coagulation Power**:
- According to the Hardy-Schulze rule, the coagulating power of an ion is related to its charge. The higher the charge of the ion, the greater its coagulating power.
- \( \text{Al}^{3+} \) has a charge of +3, while \( \text{Na}^{+} \) has a charge of +1.
- Therefore, \( \text{Al}^{3+} \) will have a greater coagulation power than \( \text{Na}^{+} \).

3. **Understanding the Reason (R)**:
- The reason states that "greater the valency of the flocculating ion added, greater is its power to cause precipitation."
- This statement is consistent with the Hardy-Schulze rule, which indicates that ions with higher charges are more effective at coagulating colloids.

4. **Conclusion**:
- Both the Assertion (A) and Reason (R) are true.
- The Reason (R) correctly explains the Assertion (A) based on the principles of the Hardy-Schulze rule.

### Final Answer:
Both Assertion (A) and Reason (R) are true, and the Reason is the correct explanation for the Assertion. Therefore, the answer is option 1.

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