Classify the following as addition and condensation polymers: Terylene, Bakelite, Polyvinyl chloride, Polythene.

Explanation

To classify the given polymers as addition or condensation polymers, we will analyze each polymer based on its structure and the process by which it is formed.

### Step-by-Step Solution:

1. **Polythene (Polyethylene)**:
- **Structure**: Polythene is formed from the monomer ethylene (C2H4), which has the structure CH2=CH2. During polymerization, the double bond in ethylene opens up, allowing the monomers to link together without the loss of any small molecules.
- **Classification**: Since there is no elimination of any by-products during the formation of polythene, it is classified as an **addition polymer**.

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