The rate determining step for the preparation of nitrobenzene from benzen is

Options

A. Removal of `overset(+)(N)O_(2)`
B. Removal of `overset(+)(N)O_(3)`
C. Formation of `overset(+)(N)O_(2)`
D. Formation of `overset(+)(N)O_(3)`

Answer

To determine the rate-determining step for the preparation of nitrobenzene from benzene, we can analyze the reaction mechanism involved in this process.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
The preparation of nitrobenzene from benzene typically involves the electrophilic aromatic substitution reaction where benzene reacts with a nitronium ion (NO₂⁺).

2. **Formation of the Electrophile**:
In the reaction, the nitronium ion (NO₂⁺) is generated from a nitrating mixture, usually consisting of concentrated nitric acid (HNO₃) and concentrated sulfuric acid (H₂SO₄). The formation of this ion is crucial as it acts as the electrophile that will attack the benzene ring.

3. **Mechanism of the Reaction**:
The mechanism can be summarized as follows:
- First, the concentrated sulfuric acid protonates the nitric acid, leading to the formation of the nitronium ion (NO₂⁺).
- Then, the nitronium ion attacks the benzene ring, leading to the formation of a sigma complex (also known as an arenium ion).
- Finally, the sigma complex loses a proton to regenerate the aromaticity of the benzene ring, yielding nitrobenzene.

4. **Identifying the Rate-Determining Step**:
The rate-determining step (RDS) is the slowest step in the reaction mechanism that controls the overall rate of the reaction. In this case, the formation of the nitronium ion (NO₂⁺) from the nitrating mixture is the slowest step because it involves the generation of a reactive electrophile.

5. **Conclusion**:
Therefore, the rate-determining step for the preparation of nitrobenzene from benzene is the formation of the nitronium ion (NO₂⁺).

### Final Answer:
The rate determining step for the preparation of nitrobenzene from benzene is the formation of NO₂⁺.

---