Which one is the appropriate reaction conditions leading to the formation of `C_(2)H_(5)Cl`?

Options

A. `C_(2)H_(6)` (excess) `+Cl_(2)overset("UV light")rarr`
B. `C_(2)H_(4)+Cl_(2) overset("dark room temperature")rarr`
C. `C_(2)H_(4)+HClrarr`
D. Both 1 and 3

Answer

To determine the appropriate reaction conditions leading to the formation of C2H5Cl (ethyl chloride), we will analyze each of the given options step by step.

### Step 1: Analyze Option A
**Reaction:** C2H6 (ethane) in excess reacts with Cl2 (chlorine) in the presence of UV light.

- **Type of Reaction:** This is a halogenation reaction of an alkane.
- **Mechanism:** The reaction occurs via a free radical mechanism. In the presence of UV light, chlorine molecules (Cl2) dissociate into chlorine free radicals (Cl•).
- **Substitution:** One hydrogen atom from ethane (C2H6) is substituted by a chlorine atom, leading to the formation of C2H5Cl (ethyl chloride) and HCl (hydrochloric acid).
- **Conclusion:** C2H5Cl is indeed formed in this reaction.

### Step 2: Analyze Option B
**Reaction:** C2H4 (ethene) reacts with Cl2 (chlorine) at room temperature in the dark.

- **Type of Reaction:** This is an addition reaction.
- **Mechanism:** Ethene (C2H4) reacts with chlorine, resulting in the addition of chlorine across the double bond.
- **Product:** The product formed is dichloroethane (C2H4Cl2), not C2H5Cl.
- **Conclusion:** C2H5Cl is not formed in this reaction.

### Step 3: Analyze Option C
**Reaction:** C2H4 (ethene) reacts with HCl (hydrochloric acid).

- **Type of Reaction:** This is also an addition reaction.
- **Mechanism:** The double bond in ethene reacts with HCl, leading to the addition of a hydrogen atom to one carbon and a chlorine atom to the other carbon.
- **Product:** The product formed is C2H5Cl (ethyl chloride).
- **Conclusion:** C2H5Cl is formed in this reaction.

### Step 4: Analyze Option D
**Option D states:** Both 1 and 3.

- From the analysis, we found that both Option A (C2H6 + Cl2 in UV light) and Option C (C2H4 + HCl) lead to the formation of C2H5Cl.
- Therefore, Option D is correct.

### Final Answer
The appropriate reaction conditions leading to the formation of C2H5Cl are given in **Option D: both 1 and 3**.

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