Polystyrene is a

Options

A. Copolymer
B. Addition polymer
C. Condensation polymer
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding Polystyrene**: Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer styrene, which is a liquid hydrocarbon that is commercially manufactured from petroleum.

2. **Polymerization Process**: The formation of polystyrene involves a process known as polymerization, where small molecules (monomers) join together to form a larger molecule (polymer).

3. **Types of Polymerization**:
- **Addition Polymerization**: This is a process where unsaturated monomers (like styrene) react to form a polymer without the loss of any small molecules.
- **Condensation Polymerization**: This involves the reaction of monomers with the elimination of small molecules (like water) during the formation of the polymer.

4. **Mechanism of Polymerization**:
- **Initiation**: The process starts with the formation of a radical that attacks the double bond in the styrene molecule, leading to the formation of a new radical.
- **Propagation**: The newly formed radical can react with another styrene molecule, creating a longer chain of the polymer. This process can repeat multiple times, leading to a high molecular weight polymer.
- **Termination**: The polymerization process ends when two radicals combine to form a stable bond, resulting in the final polymer structure.

5. **Conclusion**: Since polystyrene is formed through the addition of styrene monomers without the loss of any small molecules, it is classified as an **addition polymer**.

**Final Answer**: Polystyrene is an addition polymer.

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