On complete hydrogenation, natural rubber produces

Options

A. ethylene-propylene copolymer
B. vulcanised rubber
C. polyproylene
D. polybutylene .

Explanation

To solve the question "On complete hydrogenation, natural rubber produces," we need to analyze the process of hydrogenation of natural rubber, which is primarily composed of isoprene units.

### Step-by-Step Solution:

1. **Understanding Natural Rubber**:
- Natural rubber is a polymer made from the monomer isoprene (C5H8). The structure of isoprene contains double bonds (alkenes).

2. **Hydrogenation Process**:
- Hydrogenation is a chemical reaction that involves the addition of hydrogen (H2) to a compound. In the case of natural rubber, hydrogenation will convert the double bonds in the isoprene units into single bonds.

3. **Result of Complete Hydrogenation**:
- When all the double bonds in natural rubber are hydrogenated, the polymer structure changes. The double bonds are converted to single bonds, resulting in a saturated polymer.

4. **Identifying the Product**:
- The product of the complete hydrogenation of natural rubber is a polymer that resembles the structure of ethylene and propylene combined. This is known as ethylene-propylene copolymer.

5. **Conclusion**:
- Therefore, on complete hydrogenation, natural rubber produces **ethylene-propylene copolymer**.

### Final Answer:
The correct answer is **A) Ethylene propylene copolymer**.

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