A and B in the following reactions are respectively
(i) `CHCl_(3) overset( "Zn + H"_(2)O )(rarr) A` (ii) ` CHCl_(3) overset(Zn + HCl )(rarr)` B

Options

A. `CH_(2)Cl_(2) and CH_(4)`
B. `CH_(4) and CH_(2) Cl_(2)`
C. `"CCl"_(3) CHO and CH_(4)`
D. `"CCl"_(3) CHO and CH_(2) Cl_(2)`

Answer

To solve the problem, we need to identify the products A and B formed from the reactions of chloroform (CHCl₃) with zinc in the presence of water and hydrochloric acid, respectively.

### Step-by-Step Solution:

1. **Identify Reaction (i): CHCl₃ + Zn + H₂O → A**
- In this reaction, zinc (Zn) acts as a reducing agent in the presence of water (H₂O).
- The reaction leads to the reduction of chloroform (CHCl₃) to methane (CH₄).
- The overall reaction can be summarized as:
\[ \text{CHCl}_3 + \text{Zn} + \text{H}_2\text{O} \rightarrow \text{CH}_4 + \text{ZnCl}_2 + \text{HCl} \]
- Therefore, the product A is **methane (CH₄)**.

2. **Identify Reaction (ii): CHCl₃ + Zn + HCl → B**
- In this reaction, zinc reacts with hydrochloric acid (HCl) to form zinc chloride (ZnCl₂) and hydrogen gas (H₂).
- The zinc chloride acts as a Lewis acid and interacts with chloroform (CHCl₃).
- The reaction proceeds as follows:
- Zn reacts with HCl:
\[ \text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2 \]
- The ZnCl₂ interacts with CHCl₃, leading to the formation of dichloromethane (CH₂Cl₂):
\[ \text{CHCl}_3 + \text{ZnCl}_2 \rightarrow \text{CH}_2\text{Cl}_2 + \text{HCl} \]
- Thus, the product B is **dichloromethane (CH₂Cl₂)**.

### Final Answer:
- A = CH₄ (methane)
- B = CH₂Cl₂ (dichloromethane)