Nitrobenzene on reaction with conc `HNO_(3)//H_(2)SO_(4)` at `80-100^(@)C` forms which one of the following products .

Options

A. 1,2-dinitrobenzene
B. 1,3-dinitrobenzene
C. 1,4-dinitrobenzene
D. 1,2,4-trinitrobenzene

Explanation

To solve the problem of what product is formed when nitrobenzene reacts with concentrated nitric acid (HNO3) and sulfuric acid (H2SO4) at a temperature of 80-100°C, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are nitrobenzene (C6H5NO2), concentrated nitric acid (HNO3), and concentrated sulfuric acid (H2SO4).

2. **Understand the Reaction Conditions**: The reaction is carried out at a temperature of 80-100°C. This temperature is important as it influences the reactivity of the electrophiles generated.

3. **Formation of Electrophile**: When concentrated HNO3 and H2SO4 are mixed, they generate the nitronium ion (NO2+), which is a strong electrophile. The reaction can be summarized as:
\[ \text{HNO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{NO}_2^+ + \text{HSO}_4^- \]

4. **Electrophilic Aromatic Substitution**: Nitrobenzene contains a nitro group (-NO2) which is a deactivating group and directs incoming electrophiles to the meta position. The nitro group withdraws electron density from the aromatic ring, making the ortho and para positions less favorable for electrophilic attack.

5. **Position of Electrophilic Attack**: Given that the nitro group is a meta-directing group, the nitronium ion (NO2+) will preferentially attack the meta position of the nitrobenzene.

6. **Product Formation**: The product formed from this reaction will be 1,3-dinitrobenzene, where two nitro groups are present on the benzene ring at the 1 and 3 positions relative to each other.

### Final Answer:
The product formed when nitrobenzene reacts with concentrated HNO3 and H2SO4 at 80-100°C is **1,3-dinitrobenzene**.

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