Which of the following sets contain only addition homopolymers ?

Explanation

To determine which of the given sets contain only addition homopolymers, we need to first understand the definitions of addition polymers and homopolymers.

### Step-by-Step Solution:

1. **Understanding Addition Polymers**:
- Addition polymers are formed through chain reactions where monomers add together without the loss of any small by-products (like water or ammonia).
- Examples include polyethylene, polyvinyl chloride (PVC), and neoprene.

2. **Understanding Homopolymers**:
- Homopolymers are polymers that consist of only one type of monomer unit.
- For example, polyethylene is a homopolymer made from the monomer ethylene.

3. **Analyzing the Given Sets**:
- **Set 1**: Polythene, Natural Rubber, Cellulose
- Polythene (addition polymer, homopolymer from ethylene).
- Natural Rubber (addition polymer, homopolymer from isoprene).
- Cellulose (condensation polymer, formed by glycosidic bonds with the loss of water).
- **Conclusion**: This set contains cellulose, which is not an addition polymer.

- **Set 2**: Nylon, Polyester, Melamine Resin
- Nylon (condensation polymer, formed by amide linkages).
- Polyester (condensation polymer, formed by ester linkages).
- Melamine Resin (condensation polymer, formed by melamine and formaldehyde).
- **Conclusion**: All three are condensation polymers, so this set does not contain addition homopolymers.

- **Set 3**: Neoprene, PVC, Polythene
- Neoprene (addition polymer, homopolymer from chloroprene).
- PVC (addition polymer, homopolymer from vinyl chloride).
- Polythene (addition polymer, homopolymer from ethylene).
- **Conclusion**: All three are addition homopolymers.

4. **Final Answer**:
- The correct set that contains only addition homopolymers is **Set 3**: Neoprene, PVC, and Polythene.