Assertion : `I_(2)O_(5)` is used to detect CO.
Reason : ln `I_(2)O_(5)` the oxidation number of l is 5.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states that \( I_2O_5 \) is used to detect CO (carbon monoxide).

- **Explanation**: \( I_2O_5 \) (iodine pentoxide) can react with carbon monoxide to produce iodine and carbon dioxide. This reaction is utilized in detecting CO because the presence of CO can be indicated by the formation of iodine.

### Step 2: Analyze the Reason
The reason states that in \( I_2O_5 \), the oxidation number of iodine (I) is 5.

- **Explanation**: To determine the oxidation number of iodine in \( I_2O_5 \), we can use the following calculation:
- Let the oxidation number of iodine be \( x \).
- Oxygen has an oxidation number of \(-2\).
- The formula for \( I_2O_5 \) can be set up as follows:
\[ 2x + 5(-2) = 0 \]
\[ 2x - 10 = 0 \implies 2x = 10 \implies x = 5 \]
- Thus, the oxidation number of iodine in \( I_2O_5 \) is indeed 5.

### Step 3: Conclusion
Both the assertion and reason are true:
- The assertion is true because \( I_2O_5 \) is indeed used to detect CO.
- The reason is true because the oxidation number of iodine in \( I_2O_5 \) is 5.

However, the reason does not explain the assertion directly. The assertion is about the application of \( I_2O_5 \) in detecting CO, while the reason discusses the oxidation state of iodine, which is not directly related to the detection mechanism.

### Final Answer
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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