Plastics are polymers.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Statement**: The statement we need to evaluate is "Plastics are polymers."

2. **Defining Polymers**: Polymers are large molecules made up of repeating structural units called monomers.

3. **Monomer to Polymer Process**: When monomers undergo a chemical reaction called polymerization, they link together to form a polymer.

4. **Example of a Polymer**: One common example of a polymer is polythene (polyethylene).
- The monomer for polythene is ethene (ethylene), which has the chemical structure CH2=CH2.
- When many ethene molecules polymerize, they form polythene, represented as (CH2-CH2)n, where "n" indicates the number of repeating units.

5. **Another Example of a Polymer**: Another example is polyvinyl chloride (PVC).
- The monomer for PVC is vinyl chloride, which has the structure CH2=CHCl.
- When vinyl chloride molecules polymerize, they form PVC, represented as (CH2-CHCl)n.

6. **Conclusion**: Since both polythene and PVC are made up of repeating monomer units, they are classified as polymers. Therefore, the statement "Plastics are polymers" is true.

**Final Answer**: The statement "Plastics are polymers" is true.

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