The reactivity of ethyl chloride is :

Options

A. More or less equal to that of benzyl chloride
B. More than that of benzyl chloride
C. More or less equal to that of chlorobenzene
D. Less than that of chlorobenzene

Answer

To determine the reactivity of ethyl chloride (C2H5Cl), we need to analyze its behavior in nucleophilic substitution reactions, particularly the SN2 mechanism.

### Step-by-Step Solution:

1. **Identify the Structure of Ethyl Chloride**:
Ethyl chloride is represented as C2H5Cl. It consists of an ethyl group (C2H5) attached to a chlorine atom.

2. **Understand the Mechanism of Reaction**:
Ethyl chloride primarily undergoes nucleophilic substitution reactions via the SN2 mechanism. In this mechanism, the nucleophile attacks the carbon atom bonded to the leaving group (chlorine) from the opposite side, leading to a simultaneous bond formation and bond breaking.

3. **Consider the Steric Hindrance**:
In the case of SN2 reactions, steric hindrance plays a crucial role. The less hindered (less bulky) the carbon atom is, the more accessible it is for the nucleophile to attack. Ethyl chloride has a primary carbon, which is less hindered compared to secondary or tertiary carbons.

4. **Compare with Other Compounds**:
- **Benzyl Chloride (C6H5CH2Cl)**: This compound has a benzyl group, which is also relatively less hindered, allowing for good reactivity in SN2 reactions.
- **Chlorobenzene (C6H5Cl)**: In chlorobenzene, the chlorine is attached to a sp2 hybridized carbon in an aromatic ring, making it significantly less reactive in nucleophilic substitution due to resonance stabilization.

5. **Establish Reactivity Order**:
Based on the steric factors and the nature of the carbon atom:
- Ethyl chloride (C2H5Cl) is more reactive than chlorobenzene (C6H5Cl).
- Ethyl chloride has comparable reactivity to benzyl chloride (C6H5CH2Cl), but it is generally accepted that benzyl chloride is slightly more reactive due to the stabilization of the transition state.

6. **Conclusion**:
Therefore, the reactivity of ethyl chloride is higher than that of chlorobenzene and comparable to benzyl chloride. The correct option regarding the reactivity of ethyl chloride is that it is more reactive than chlorobenzene and less than or equal to benzyl chloride.

### Final Answer:
The reactivity of ethyl chloride is more than chlorobenzene and comparable to benzyl chloride.

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