In an electrophilic substitution reaction of nitrobenzene, the presence of nitro group

Options

A. deactivates the ring by inductive effect.
B. activates the ring by inductive effect.
C. decreases the charge density at ortho and para position of the ring relative to meta position by resonance.
D. increases the charge density at meta position relative to the ortho and para positions of the ring by resonance.

Answer

To solve the question regarding the effect of the nitro group on the electrophilic substitution reaction of nitrobenzene, we will analyze the behavior of the nitro group in relation to the benzene ring.

### Step-by-Step Solution:

1. **Understanding the Structure of Nitrobenzene**:
- Nitrobenzene consists of a benzene ring with a nitro group (-NO2) attached to it. The benzene ring is known for its electron-rich nature due to the presence of π-bonds.

2. **Identifying the Nature of the Nitro Group**:
- The nitro group is an electron-withdrawing group due to its strong -I (inductive) and -M (mesomeric or resonance) effects. This means it pulls electron density away from the benzene ring.

3. **Effect of the Nitro Group on Electrophilic Substitution**:
- In electrophilic substitution reactions, an electrophile attacks the benzene ring. The presence of the nitro group affects where this electrophile is likely to attack.

4. **Analyzing the Resonance Structures**:
- When considering resonance structures, the nitro group can stabilize certain positions on the benzene ring. The resonance structures show that the electron density at the ortho and para positions decreases due to the positive charge that develops in these positions when the nitro group withdraws electrons.

5. **Comparing Ortho, Para, and Meta Positions**:
- The nitro group has a stronger -M effect at the ortho and para positions compared to the meta position. This means that the electron density is significantly reduced at the ortho and para positions relative to the meta position.

6. **Conclusion**:
- Therefore, the presence of the nitro group decreases the charge density at the ortho and para positions of the benzene ring relative to the meta position. This leads us to conclude that the correct answer is:
- **C: Decrease the charge density at ortho and para position of the ring relative to meta position by resonance.**