Ethylene reacts with bromine to from

Options

A. Chloromethane
B. Ethylene dibromide
C. Cyclohexane
D. 1 -bromo propane

Explanation

To solve the question of how ethylene reacts with bromine and what the product is, we can follow these steps:

### Step 1: Identify the Reactants
Ethylene is an alkene with the chemical formula C2H4, which can be represented as:
\[ \text{CH}_2= \text{CH}_2 \]
Bromine (Br2) is a diatomic molecule.

### Step 2: Understand the Reaction Mechanism
When ethylene reacts with bromine, the double bond in ethylene undergoes an addition reaction. The reaction proceeds through the formation of a bromonium ion intermediate.

### Step 3: Formation of the Bromonium Ion
1. The double bond in ethylene attacks one of the bromine atoms, leading to the formation of a cyclic bromonium ion. This intermediate can be represented as:
\[ \text{CH}_2^+ - \text{Br} - \text{CH}_2^+ \]
Here, the bromine atom forms a bridge over the two carbon atoms.

### Step 4: Nucleophilic Attack
2. The bromide ion (Br-) that was generated when the bromine molecule dissociated now attacks the more substituted carbon of the bromonium ion. This results in the opening of the bromonium ion and the formation of the final product.

### Step 5: Write the Final Product
The final product of the reaction between ethylene and bromine is 1,2-dibromoethane, which can be represented as:
\[ \text{CH}_2\text{Br} - \text{CH}_2\text{Br} \]

### Conclusion
Thus, the reaction of ethylene with bromine yields 1,2-dibromoethane.