In the nitration of benzene with conc. `HNO_(3)` and conc `H_(2)SO_(4)` the electrophile acting group is

Options

A. `NO_(2)`
B. `NO`
C. `overset(+)(N)O_(2)`
D. `NO_(3)^(-)`

Answer

To determine the electrophile acting in the nitration of benzene with concentrated nitric acid (HNO3) and concentrated sulfuric acid (H2SO4), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction Conditions**:
- The nitration of benzene involves the use of concentrated nitric acid (HNO3) and concentrated sulfuric acid (H2SO4).

2. **Role of Sulfuric Acid**:
- Concentrated sulfuric acid acts as a dehydrating agent. It helps in the generation of the nitronium ion (NO2^+) from nitric acid.

3. **Formation of the Electrophile**:
- When HNO3 reacts with H2SO4, the sulfuric acid donates a proton (H^+) to the nitric acid. This results in the formation of the nitronium ion (NO2^+) and water.
- The reaction can be summarized as follows:
\[ HNO_3 + H_2SO_4 \rightarrow NO_2^+ + H_2O + HSO_4^- \]

4. **Identifying the Electrophile**:
- The nitronium ion (NO2^+) is a powerful electrophile that will attack the benzene ring in the nitration process.
- Therefore, the electrophile acting in the nitration of benzene is the nitronium ion (NO2^+).

### Final Answer:
The electrophile acting in the nitration of benzene with concentrated HNO3 and H2SO4 is the nitronium ion (NO2^+).

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