Which of the following contains isoprene units?

Options

A. Natural rubber
B. Nylon-6,10
C. Dacron
D. Polyethylene

Answer

To determine which of the given options contains isoprene units, we can follow these steps:

### Step 1: Understand Isoprene
Isoprene is a diene with the chemical formula C5H8, specifically known as 2-methyl-1,3-butadiene. Its structure can be represented as:
\[ \text{CH}_2=C(CH_3)-CH=CH_2 \]

### Step 2: Identify the Polymers
We need to analyze the options provided (though not explicitly listed in the question, we can assume common polymers):
1. Natural Rubber
2. Nylon 6
3. Dacron
4. Polyethylene

### Step 3: Analyze Each Polymer
- **Natural Rubber**: This is a polymer made from isoprene units. It is formed by the polymerization of isoprene (C5H8) and is known for its elasticity.
- **Nylon 6**: This is a synthetic polymer made from caprolactam, not isoprene.
- **Dacron**: This is a polyester made from ethylene glycol and terephthalic acid, not isoprene.
- **Polyethylene**: This is made from ethylene (C2H4) and does not contain isoprene units.

### Step 4: Conclusion
From the analysis, we conclude that the only polymer that contains isoprene units is **Natural Rubber**.

### Final Answer
The correct option that contains isoprene units is **Natural Rubber**.

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