In the preparation of alkyl halide from alkene and halogen which of the following reaction is involved

Options

A. electrophilic addition
B. nuclephilic addition
C. electrophilie substitution
D. nucleophilic substitution

Explanation

To prepare an alkyl halide from an alkene and halogen, we need to understand the type of reaction involved. Here’s a step-by-step breakdown of the process:

### Step 1: Identify the Reactants
We start with an alkene (C=C) and a halogen (X2, where X can be Cl or Br).

**Hint:** Look for the double bond in the alkene, which is crucial for the reaction.

### Step 2: Electrophilic Attack
The alkene has a high electron density due to the presence of the pi bond. The halogen (X2) acts as an electrophile. The pi electrons of the alkene attack one of the halogen atoms, leading to the formation of a cyclic intermediate.

**Hint:** Remember that the double bond in the alkene is what allows it to react with the halogen.

### Step 3: Formation of a Cyclic Intermediate
When the alkene attacks the halogen, a cyclic bromonium or chloronium ion is formed. This three-membered ring structure is a key feature of the reaction.

**Hint:** Visualize the cyclic structure that forms; it helps in understanding the mechanism.

### Step 4: Nucleophilic Attack
The other halogen atom (which is now a bromide or chloride ion) attacks the more substituted carbon of the cyclic intermediate, leading to the opening of the ring.

**Hint:** The nucleophile (the halide ion) will attack the carbon that is more stable (more substituted).

### Step 5: Formation of Alkyl Halide
After the nucleophilic attack, the final product is an alkyl halide (R-X), where X is the halogen that has been added to the alkene.

**Hint:** Check the final structure to ensure that the halogen is correctly added to the alkyl chain.

### Conclusion
The reaction involved in the preparation of alkyl halides from alkenes and halogens is an **Electrophilic Addition Reaction**.

**Final Answer:** The correct option is **A: Electrophilic Addition Reaction**.

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