A: Nitrobenzene on reduction with `Zn//NaOH//Delta` gives hydrazobenzene.
R: Nitrobenzene on reduction with Sn/HCI gives aniline.

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 solve the question, we will analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states that nitrobenzene on reduction with zinc (Zn), sodium hydroxide (NaOH), and heat gives hydrazobenzene.

- **Chemical Reaction**:
Nitrobenzene (C6H5NO2) reacts with zinc and NaOH under heat. The reaction can be represented as follows:
\[ 2 \, \text{C}_6\text{H}_5\text{NO}_2 + \text{Zn} + \text{NaOH} \xrightarrow{\Delta} \text{C}_6\text{H}_5\text{N}=\text{N}\text{C}_6\text{H}_5 + \text{by-products} \]
- **Conclusion**: This reaction indeed produces hydrazobenzene (C6H5N=N C6H5). Therefore, the assertion is **true**.

### Step 2: Analyze the Reason (R)
The reason states that nitrobenzene on reduction with tin (Sn) and hydrochloric acid (HCl) gives aniline.

- **Chemical Reaction**:
Nitrobenzene (C6H5NO2) reacts with tin and hydrochloric acid to produce aniline (C6H5NH2). The reaction can be represented as follows:
\[ \text{C}_6\text{H}_5\text{NO}_2 + \text{Sn} + \text{HCl} \rightarrow \text{C}_6\text{H}_5\text{NH}_2 + \text{by-products} \]
- **Conclusion**: This reaction indeed produces aniline. Therefore, the reason is also **true**.

### Step 3: Determine the Relationship Between A and R
While both the assertion and the reason are true, we need to evaluate whether the reason correctly explains the assertion.

- The assertion discusses the formation of hydrazobenzene from nitrobenzene using Zn/NaOH, while the reason discusses the formation of aniline from nitrobenzene using Sn/HCl.
- The two reactions are different and do not directly explain each other.

### Final Conclusion
- The assertion (A) is true.
- The reason (R) is true, but it does not provide the correct explanation for the assertion (A).

### Answer
The correct answer is: **Assertion is true, Reason is true, but Reason is not the correct explanation for Assertion.**

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