Which of these monomers are combined to form polythene?

Options

A. Ethane
B. Ethylene
C. Methane
D. Methylene

Explanation

### Step-by-Step Solution:

1. **Identify the Monomer of Polythene**:
- The first step is to determine what a monomer is. A monomer is a small molecule that can join together with other monomers to form a polymer.
- In the case of polythene, the specific monomer that is used is ethylene.

2. **Chemical Structure of Ethylene**:
- The chemical formula for ethylene is \( \text{C}_2\text{H}_4 \), which can also be represented as \( \text{CH}_2=\text{CH}_2 \).
- This shows that ethylene has a double bond between the two carbon atoms.

3. **Polymerization Process**:
- When ethylene undergoes polymerization, the double bond between the carbon atoms breaks, allowing the ethylene molecules to link together.
- This process leads to the formation of long chains of repeating units of ethylene, resulting in polythene.

4. **Chemical Structure of Polythene**:
- The resulting structure of polythene can be represented as \( \text{-(CH}_2\text{-CH}_2\text{)}_n \), where \( n \) indicates the number of repeating units.
- This shows that polythene is made up of many ethylene units joined together.

5. **Conclusion**:
- Therefore, the monomer that is combined to form polythene is ethylene. The correct answer to the question is ethylene.

### Final Answer:
The monomer combined to form polythene is **ethylene**.

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