Class 8 Science Chapter 3 MCQ with Answers
Mcq Questions For Class 8 sciences chapter 3 Synthetic Fibres And Plastics
Synthetic fibres and plastics, like natural fi-bres, are made of very large units called polymers. Polymers are made up of many smaller units. While natural fibres are obtained from plants and animals, synthetic fibres are obtained by chemical processing of petrochemicals. natural fibres, these fibres can also be woven into fabrics. Synthetic fibres find uses ranging from many household articles like ropes,buckets, furniture, containers, etc., to highly specialised uses in aircrafts, ships, space-crafts, healthcare, etc. Depending upon the types of chemicals used for manufacturing synthetic fibres, they are called Rayon, Nylon, Polyester and Acrylic. The different types of fibres differ from one another in their strength, water absorbing capacity, nature of burning, cost, durability
etc.
Here you will find a list of Most important Multiple Choice Questions on Synthetic fibres and plastics with answer for competitive exams like CBSE Class 8 science chapter 3 MCQs . These frequently asked sample questions on are given with correct choice of answer that you can check instantly. Presently we have added more than 30 MCQ questions on class 8 science chapter 3 for your practice. We will keep adding more questions and provide this question bank in PDF format, so that you can download them instantly in E-book style.
Ncert Class 8 Science Chapter 3 MCQs
1. Which of the following is synthetic fibre?
(a) Nylon
(b) Cotton
(c) Silk
(d) Wood
Answer: (a)
2. Polymers are made up of small units called__________
(a) layers
(b) molecules
(c) cells
(d) monomers
Answer: (d)
3. Wood pulp is used to make___________
(a) plastic
(b) wool
(c) jute
(d) rayon
Answer: (d)
4. Melamine is_____________
(a) thermoplastic polymer
(b) thermosetting polymer
(c) fibre
(d) elastomer
Answer: (b)
5. Which of the following cannot be recycled?
(a) Toys
(b) Cooker handles
(c) Carry bags
(d) Plastic chair
Answer: (b)
6. Identify the product based on the given features.
I. It is a man-made product.
II. It has a linear arrangement of monomer units.
III. It is used for making goods like toys, combs, containers, etc.
(a) Lycra
(b) Rayon
(c) Thermosets
(d) Thermoplastics
Answer: (d)
7. A polymer is a large molecule composed of many repeated units. What is a polyester composed of__________
(a) Ether
(b) Cellulose
(c) Amino acids
(d) Ester
Answer: (d)
8. One of the advantages of nylon over rayon is that nylon________
(a) wrinkle free.
(b) low elasticity
(c) natural fibre.
(d) good conductor of electricity
Answer: (a)
9. Fibres of _______ resemble that of silk and hence, it is popularly known as ‘artificial silk’.
(a) acrylic
(b) polyester
(c) rayon
(d) nylon
Answer: (C)
10. Identify the type of plastic that can best be used to make electrical switches.
(a) PVC
(b) Polythene
(c) PET
(d) Bakelite
Answer: (d)
11. Which of the following statements incorrect?
I . Cellulose is a polymer that is made up of a large number of small glucose molecules joined one after the other.
II . Wood contains a very less amount of cellulose polymer.
III. The small molecules that join together to form a polymer are called monomers.
(a) Only I
(b) Both I and II
(c) Only II
(d) Both II and III
Answer: (c)
12. Which of the following is not a property of nylon?
(a) Nylon is a thermoplastic polymer.
(b) Nylon fibers are fairly strong and elastic.
(c) Nylon fibers are lightweight and lustrous.
(d) It is cheaper than natural silk and can be woven like silk fiber.
Answer: (d)
13. Which of the following is a fire-resistant plastic and is used to coat the uniforms of firemen?
(a) Teflon
(b) Melamine
(c) Bakelite
(d) PVC
Answer: (b)
14. Which of the following plastics is used for making electric switches, plugs and sockets?
(a) Polythene
(b) Polyvinyl chloride
(c) Melamine
(d) Bakelite
Answer: (d)
15. A plastic that can be softened repeatedly by heating and can be moulded into different shapes again and again is called a thermoplastic. Which of the following plastics are thermoplastics?
A. Polythene
B. Bakelite
C. PVC
D. Melamine
(a) Both A and B
(b) Both A and C
(c) Both A and D
(d) Both B and C
Answer: (b)
16. Which of the following is natural fibre obtained from plants?
(a) Cotton
(b) Wool
(c) Rayon
(d) Ketone
Answer: (a)
17. The plastic which cannot be recycled is____________
(a) jute
(b) rayon
(c) petrochemicals
(d) bakelite
Answer: (d)
18. Fibre produced in factories is called____________
(a) man-made fibre
(b) natural fibre
(c) synthetic fibre
(d) both (a) and (c)
Answer: (d) both (a) and (c)
19. The strongest synthetic fibre is________
(a) nylon
(b) rayon
(c) polyester
(d) acrylic
Answer: (a)
20. ____ is used for making electrical switches ?
(a) Melamine
(b) PVC
(c) Bakelite
(d) all
Answer: (c) Bakelite
21. The uniforms of firemen have coating of ____ plastic to make them flame resistant ?
(a) Melamine
(b) PVC
(c) Bakelite
(d) None of the above
Answer: (a)
22._____ is biodegradable ?
(a) Paper
(b) Plastic bags
(c) Metal cans
(d) all
Answer: (c)
23. A polymer is a large molecule composed of many repeated units. What is a polyester composed of________
(a) Ether
(b) Cellulose
(c) Amino acids
(d) Ester
Answer: (d)
24. Which of the following is not manufactured from high-density polythene?
(a) Containers
(b) Pipes
(c) Candles
(d) Toys
Answer: (c)
25. Terylene is a popular form of_________
(a) Polyester
(b) Monomer
(c) Plastic
(d) Nylon
Answer: (a)
26. Select the correct option from the given statements.
(a) Polymers cannot form fibres
(b) Polymers can be both natural and synthetic
(c) Polymer is a natural substance
(d) Polymer is a synthetic substance
Answer: (b)
27. Pickles are stored in plastic bottles mainly because they are_________
(a) non-biodegradable
(b) good insulators
(c) durable
(d) non-reactive
Answer: (d)
28. Fibres of _______ resemble that of silk and hence, it is popularly known as ‘artificial silk’.
(a) acrylic
(b) polyester
(c) rayon
(d) nylon
Answer: (c)
29. Which of the following fibres is used for making parachutes?
(a) Plastic
(b) Terelyne
(c) Nylon
(d) Steel
Answer: (c)
30. Which of the following material is a mixture of two fibres?
(a) Jute
(b) Polywool
(c) Polyester
(d) Nylon
Answer: (b)