Class 8 Science – Chapter 3
Synthetic Fibres and Plastics
Important Exam Questions (VSA / SA / LA)

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🔹 Very Short Answer Questions (1 Mark)

1. Name one synthetic fibre.

Answer: Nylon

2. What is plastic?

Answer: Plastic is a synthetic material made from polymers.

3. Name the plastic used to make electrical switches.

Answer: Bakelite

4. Is plastic biodegradable?

Answer: No

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🔹 Short Answer Questions (2–3 Marks)

5. What are synthetic fibres? Give two examples.

Answer: Synthetic fibres are man-made fibres prepared using chemicals.
Examples: Nylon and Polyester.

6. Why is nylon called a strong fibre?

Answer: Nylon is strong because it has high tensile strength, is lightweight, durable and resistant to wear and tear.

7. Write two differences between thermoplastic and thermosetting plastic.

Answer:
• Thermoplastics can be reshaped on heating; thermosetting plastics cannot.
• Thermoplastics soften on heating; thermosetting plastics do not.

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🔹 Long Answer Questions (4–5 Marks)

8. Explain different types of synthetic fibres.

Answer:
• Rayon: Made from wood pulp, looks like silk.
• Nylon: Strong fibre used in ropes and parachutes.
• Polyester: Used in clothes, does not wrinkle easily.
• Acrylic: Used as artificial wool.

9. Why should plastics be avoided? Mention harmful effects.

Answer:
• Plastics are non-biodegradable.
• They cause soil and water pollution.
• Burning plastics releases poisonous gases.
• They harm animals when swallowed.

10. Explain the principle of 4R with respect to plastics.

Answer:
• Reduce: Minimise plastic use.
• Reuse: Use plastic items again.
• Recycle: Convert waste plastic into useful products.
• Recover: Recover energy from plastic waste.

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✅ High-probability exam questions based on CBSE pattern