Which of the following is the monomer for natural rubber?

Options

A.
B. `CH_2=CH-CH=CH_2`
C. `CH_3-CH-C=CH_2`
D. All of the above

Answer

To determine the monomer for natural rubber, we can follow these steps:

### Step 1: Understand the Concept of Monomers and Polymers
- A monomer is a small molecule that can join together with other similar molecules to form a larger structure known as a polymer.

### Step 2: Identify Natural Rubber
- Natural rubber is a polymer that is derived from the latex of rubber trees. It is primarily composed of repeating units.

### Step 3: Identify the Monomer of Natural Rubber
- The specific monomer that makes up natural rubber is known as isoprene. Isoprene has the chemical formula C5H8.

### Step 4: Confirm the Structure of Isoprene
- The structure of isoprene can be represented as follows:
- It consists of a five-carbon chain with two double bonds (C=C).

### Step 5: Conclusion
- Therefore, the monomer for natural rubber is isoprene.

### Final Answer:
The monomer for natural rubber is **isoprene**.

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