The product formed when benzene is nitrated by fuming nitric acid is

Options

A. m-dinitrobenzene
B. Nitrobenzene
C. Sym-trinitrobenzene
D. None of these

Explanation

To determine the product formed when benzene is nitrated by fuming nitric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
The reactants in this reaction are benzene (C6H6) and fuming nitric acid (HNO3). Fuming nitric acid is concentrated nitric acid that contains nitrogen dioxide (NO2) dissolved in it.

2. **Understand the Nitration Process**:
Nitration of benzene involves the substitution of a hydrogen atom on the benzene ring with a nitro group (NO2). This is an electrophilic aromatic substitution reaction.

3. **Formation of the Electrophile**:
In fuming nitric acid, the nitronium ion (NO2+) is generated as the active electrophile. The reaction can be represented as:
\[ HNO3 + H2SO4 \rightarrow NO2^+ + HSO4^- + H2O \]
Here, sulfuric acid (H2SO4) is often used as a catalyst to generate the nitronium ion.

4. **Electrophilic Attack**:
The generated nitronium ion (NO2+) attacks the benzene ring. The reaction can be depicted as:
\[ C6H6 + NO2^+ \rightarrow C6H5NO2 + H^+ \]
This results in the formation of nitrobenzene (C6H5NO2) and a proton (H+).

5. **Final Product**:
The final product of the reaction is nitrobenzene.

### Conclusion:
The product formed when benzene is nitrated by fuming nitric acid is **nitrobenzene (C6H5NO2)**.

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