Assertion : `Fe^(+3)` is not valid for Brown Ring Test.
Reason : BeCause `NO_(3)^(-)` first convert into `NO_(2)^(-)`

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 asertion and reason are false.

Explanation

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

### Step 1: Understand the Assertion
The assertion states that `Fe^(+3)` is not valid for the Brown Ring Test.

**Explanation**: The Brown Ring Test is used to detect the presence of nitrate ions (`NO3^(-)`) in a solution. In this test, ferrous ions (`Fe^(+2)`) are required because they are oxidized to ferric ions (`Fe^(+3)`) during the reaction. If we start with `Fe^(+3)`, there would be no ferrous ions to oxidize, and hence the test would not yield a brown ring. Therefore, the assertion is **true**.

### Step 2: Understand the Reason
The reason states that `NO3^(-)` first converts into `NO2^(-)`.

**Explanation**: In the Brown Ring Test, `NO3^(-)` is reduced to nitric oxide (`NO`), not to `NO2^(-)`. The reduction of `NO3^(-)` involves a decrease in the oxidation state of nitrogen and the removal of oxygen, leading to the formation of `NO`. Therefore, the statement that `NO3^(-)` first converts into `NO2^(-)` is **false**.

### Step 3: Conclusion
Based on the analysis:
- The assertion is **true**.
- The reason is **false**.

Thus, the correct answer is that the assertion is true, and the reason is false.

### Final Answer
The correct option is C: Assertion is true, Reason is false.

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