Trichloroacetaldehyde $CCl_3CHO$ reacts with chlorobenzene in the presence of sulphuric acid produces :

Question

Accepted Answer

Trichloroacetaldehyde ($CCl_3CHO$) reacts with chlorobenzene in the presence of sulfuric acid to produce a specific compound. Let's analyze why Option 1 is the correct answer and why the other options are incorrect.

### Explanation for Option 1: $CCl_3CH(C_6H_4Cl)_2$

1. **Mechanism of Reaction:**
   - Trichloroacetaldehyde ($CCl_3CHO$) is a highly reactive compound due to the presence of the electron-withdrawing trichloromethyl group ($CCl_3$) and the aldehyde group ($CHO$).
   - In the presence of sulfuric acid, which acts as a catalyst, the reaction proceeds via an electrophilic aromatic substitution mechanism.
   - The $CCl_3CHO$ undergoes activation by the acid, forming a more electrophilic species that can react with chlorobenzene.
   - The reaction involves the substitution of hydrogen atoms on the aromatic ring of chlorobenzene with the activated trichloroacetaldehyde, leading to the formation of $CCl_3CH(C_6H_4Cl)_2$.

2. **Product Formation:**
   - The product $CCl_3CH(C_6H_4Cl)_2$ indicates that two chlorobenzene rings are attached to the central carbon of the trichloroacetaldehyde, consistent with the expected outcome of the reaction mechanism.

### Explanation for Why Other Options are Incorrect:

1. **Option 2: $C(Cl_2)=C(C_6H_5Cl)_2$**
   - This option suggests the formation of a compound with a double bond between carbon atoms, which is not feasible in this reaction context. The reaction involves substitution, not the formation of a double bond.

2. **Option 3: $C_6H_4(Cl)CH(OH)C_6H_4(Cl)$**
   - This option implies the formation of a diol (two hydroxyl groups), which is unlikely given the reaction conditions. The presence of sulfuric acid would not favor the formation of an alcohol group in this context.

3. **Option 4: $C(C_6H_4Cl)_3$**
   - This option suggests the attachment of three chlorobenzene rings to a single carbon atom, which is not supported by the reaction mechanism. The steric hindrance and electronic factors make this structure improbable.

In conclusion, Option 1 is the correct answer because it aligns with the expected electrophilic aromatic substitution mechanism facilitated by sulfuric acid, leading to the formation of $CCl_3CH(C_6H_4Cl)_2$. The other options do not fit the reaction conditions or expected chemical behavior.