Which of the following is a semisynthetic polymer?

Options

A. Natural rubber
B. Gun cotton
C. Cellulose
D. Nucleic acids

Answer

To determine which of the following is a semisynthetic polymer, we need to understand what a semisynthetic polymer is. A semisynthetic polymer is derived from natural polymers that have been chemically modified.

### Step-by-Step Solution:

1. **Define Semisynthetic Polymer**:
- A semisynthetic polymer is created by chemically modifying a natural polymer. This involves reacting a natural polymer with a chemical reagent to produce a new polymer.

2. **Identify Types of Polymers**:
- **Natural Polymers**: These are polymers that occur in nature without any modification. Examples include natural rubber, cellulose, and nucleic acids.
- **Synthetic Polymers**: These are entirely man-made and do not occur in nature. Examples include nylon and polyester.
- **Semisynthetic Polymers**: These are derived from natural polymers through chemical modification. An example is cellulose nitrate, which is made by nitrating cellulose.

3. **Analyze the Given Options**:
- **Natural Rubber**: This is a natural polymer and not semisynthetic.
- **Gun Cotton (Cellulose Nitrate)**: This is derived from cellulose (a natural polymer) by replacing some of its hydroxyl (-OH) groups with nitro (-NO2) groups. Thus, it is a semisynthetic polymer.
- **Cellulose**: This is a natural polymer and not modified.
- **Nucleic Acid**: This is also a natural polymer and not modified.

4. **Conclusion**:
- Among the options, **Gun Cotton (Cellulose Nitrate)** is the semisynthetic polymer because it is produced by chemically modifying cellulose.

### Final Answer:
The semisynthetic polymer among the options is **Gun Cotton (Cellulose Nitrate)**.