A : `HNO_(2)` acts as reducing agent only.
R : `HNO_(2)` oxidises to `HNO_(3)` only but not reduce by any reducing agent.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To analyze the statements A and R regarding `HNO_(2)`, we will break down the information step by step.

### Step 1: Understanding the Oxidation State of Nitrogen in `HNO_(2)`

In `HNO_(2)`, we need to determine the oxidation state of nitrogen (N). The formula for calculating oxidation states is as follows:

- The oxidation state of hydrogen (H) is +1.
- The oxidation state of oxygen (O) is -2.

Let the oxidation state of nitrogen be x. The equation can be set up as follows:

\[ 1 + x + 2(-2) = 0 \]

This simplifies to:

\[ 1 + x - 4 = 0 \implies x - 3 = 0 \implies x = +3 \]

Thus, the oxidation state of nitrogen in `HNO_(2)` is +3.

### Step 2: Evaluating the Reducing Agent Property of `HNO_(2)`

A reducing agent is a substance that can donate electrons to another substance, thereby reducing it while itself being oxidized. Since the oxidation state of nitrogen in `HNO_(2)` is +3, it can potentially be oxidized further to a higher oxidation state, such as +4 or +5.

The possible oxidation states for nitrogen are from +5 (in `HNO_(3)`) down to -3. Therefore, `HNO_(2)` can act as a reducing agent because it can lose electrons and be oxidized to `HNO_(3)`.

### Step 3: Analyzing the Statement R

The statement R claims that `HNO_(2)` oxidizes to `HNO_(3)` only and does not reduce by any reducing agent. However, since we established that `HNO_(2)` can act as a reducing agent, this statement is incorrect.

`HNO_(2)` can indeed be oxidized to `HNO_(3)`, but it can also undergo reduction reactions under certain conditions. Therefore, the claim that it does not reduce by any reducing agent is false.

### Conclusion

- Statement A is **correct**: `HNO_(2)` acts as a reducing agent.
- Statement R is **incorrect**: `HNO_(2)` can oxidize to `HNO_(3)` but can also reduce under certain conditions.

### Final Answer

A is true, and R is false.

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