Assertion `(A)`: Concentration of `H_2O_2` is expressed in volume.
Reason `(R)` :Volume strength = Normality `xx 5.6`.

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 solve the assertion-reason question, we will analyze both the assertion and the reason step by step.

### Step 1: Analyze the Assertion
The assertion states that the concentration of \( H_2O_2 \) (hydrogen peroxide) is expressed in volume.

- **Explanation**: In chemistry, the concentration of hydrogen peroxide is often expressed in terms of volume strength. Volume strength indicates how much volume of oxygen gas is produced when one volume of hydrogen peroxide decomposes. Therefore, the assertion is correct.

### Step 2: Analyze the Reason
The reason provided states that volume strength is equal to normality multiplied by 5.6.

- **Explanation**: This statement is also correct. The formula \( \text{Volume Strength} = \text{Normality} \times 5.6 \) is a valid relationship in the context of hydrogen peroxide. The factor 5.6 comes from the molar volume of a gas at standard temperature and pressure (STP), which is approximately 22.4 liters for one mole of gas. Since hydrogen peroxide decomposes to produce oxygen, this relationship holds true.

### Step 3: Determine the Relationship Between Assertion and Reason
Now, we need to determine if the reason provided is the correct explanation for the assertion.

- **Analysis**: While both the assertion and the reason are correct statements, the reason does not directly explain why the concentration of \( H_2O_2 \) is expressed in volume. The assertion is about the expression of concentration, while the reason gives a mathematical relationship. Therefore, the reason is not the correct explanation for the assertion.

### Conclusion
Both the assertion and the reason are correct, but the reason does not explain the assertion. Thus, the answer to the question is that both statements are true, but the reason is not the correct explanation for the assertion.

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

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