The polymers can be classified on the basis of their mode of formation as

Options

A. As copolymers
B. As condensation polymers only
C. As addition polymers only
D. Both as addition and condensation polymers

Answer

To classify polymers based on their mode of formation, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Polymers**:
- Polymers are large molecules made up of repeating structural units called monomers. They can be formed through different chemical processes.

2. **Modes of Formation**:
- Polymers can be classified based on how they are formed. The two primary modes of formation are:
- **Addition Polymerization**: In this process, monomers add together without the loss of any small molecule (like water). The polymer grows by the successive addition of monomer units. An example of this is polyethylene, which is formed by the addition of ethylene monomers.
- **Condensation Polymerization**: This process involves the joining of monomers with the elimination of a small molecule, often water. An example is Nylon-6, which is formed by the reaction of specific monomers that release water as a byproduct.

3. **Examples**:
- **Addition Polymers**: Polyethylene, Polystyrene, and Polyvinyl Chloride (PVC).
- **Condensation Polymers**: Nylon-6, Dacron (polyester), and Bakelite.

4. **Conclusion**:
- Based on the mode of formation, polymers can be classified into two categories: **Addition Polymers** and **Condensation Polymers**.

### Final Answer:
Polymers can be classified on the basis of their mode of formation as **Addition Polymers** and **Condensation Polymers**.

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