The reactivities of methyl chloride, propyl chloride and chlorobenzene towards solvolysis are in the order

Options

A. Methyl choride `gt` propyl chloride `gt` chlorobenzene
B. Propyl chloride `gt` Methyl choride `gt` chlorobenzene
C. Methyl choride `gt`chlorobenzene`gt` propyl chloride
D. Chlorobenzene`gt`propyl chloride `gt` Methyl choride

Explanation

To determine the reactivities of methyl chloride (CH3Cl), propyl chloride (C3H7Cl), and chlorobenzene (C6H5Cl) towards solvolysis, we need to analyze the stability of the carbocations formed during the reaction. Solvolysis involves the reaction of alkyl halides with a solvent (usually water) to form alcohols and other products.

### Step-by-Step Solution:

1. **Understanding Solvolysis**:
- Solvolysis is a nucleophilic substitution reaction where the solvent acts as a nucleophile. In this case, water will attack the carbon atom bonded to the chlorine atom after the C-Cl bond breaks.

2. **Formation of Carbocations**:
- The first step in solvolysis is the formation of a carbocation. The stability of the carbocation significantly influences the reactivity of the alkyl halide.
- Methyl chloride (CH3Cl) will form a methyl carbocation (CH3+).
- Propyl chloride (C3H7Cl) will form a propyl carbocation (C3H7+).
- Chlorobenzene (C6H5Cl) will not easily form a carbocation due to resonance stabilization of the chlorobenzene structure.

3. **Stability of Carbocations**:
- Methyl carbocation (CH3+) is a primary carbocation and is less stable.
- Propyl carbocation (C3H7+) is also a primary carbocation but has more alkyl groups that can provide +I (inductive) effect, making it slightly more stable than methyl.
- Chlorobenzene does not form a carbocation readily because the resonance in the benzene ring stabilizes the structure, making it less reactive towards solvolysis.

4. **Comparing Reactivities**:
- Since the stability of the carbocation determines the reactivity, we can rank the reactivities based on the stability of the carbocations formed:
- Propyl chloride (C3H7Cl) > Methyl chloride (CH3Cl) > Chlorobenzene (C6H5Cl).
- Therefore, the order of reactivity towards solvolysis is:
- **Propyl chloride > Methyl chloride > Chlorobenzene**.

### Final Answer:
The reactivities of methyl chloride, propyl chloride, and chlorobenzene towards solvolysis are in the order:
**Propyl chloride > Methyl chloride > Chlorobenzene**.