NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibers and Plastics
NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibers and Plastics: The experts have prepared the solutions for Class 8 Science Chapter 3 Synthetic Fibers and Plastics which includes all the solutions of the questions present in the textbook. Students must go through the Class 8 Science Chapter 3 questions answer to understand the basic concepts of this topic. The NCERT solutions include examples, detailed explanations, important questions, etc. The class 8 Science Chapter 3 solutions include questions on Synthetic fibers and Plastics, their sources, types of fibers, their uses, natural fibers, artificial fibers, uses, and qualities of plastics. After going through these NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibers and Plastics, candidates will be able to understand the topics included in this chapter.
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Topics Included in Class 8 Science Chapter 3 Question Answer
Students can check the topics included in Science Class 8 Chapter 3 question answers in below
Introduction to Synthetic Fibers and Plastics: This section includes synthetic fibers and plastics, explaining their types, properties, and applications.
Natural and Synthetic Fibers: This section includes the benefits and drawbacks of both fibers and compares these two.
Uses of Synthetic Fibers: This section explores the various applications of synthetic fibers, including their use in clothing, carpets, and ropes.
Manufacture of Synthetic Fibers: This section talks about the methods used to produce synthetic fibers, including polymerization and spinning.
Properties of Synthetic fibers: This section describes the fundamental properties of synthetic fibers, such as strength, elasticity, and durability.
Plastics: This section examines the different types of plastics and details their properties and common uses.
Problems Caused by Plastic Waste: This section addresses the environmental issues caused by plastic waste, such as pollution and ecological harm
Read More: NCERT Solutions for Class 8 Science Chapter 1
Class 8 Science Chapter 3 Question Answer
Students preparing for CBSE board exam can check the class 8 science chapter 3 question answer for Synthetic Fibers and Plastics below. Candidates are advised to read these science class 8 chapter 3 question answers while preparing for the board examination.
Question 1. Explain why some fibers are called synthetic.
Answer: Instead of occurring naturally, people create synthetic fibers using chemicals. They’re made up of tiny pieces that link to make long chains. Some standard synthetic fibers include nylon, rayon, acrylic, and polyester.
Read More: NCERT Solutions for Class 8 Science Chapter 2
Question 2. Mark the correct answer.
Rayon is different from synthetic fibers because
(a) it has a silk-like appearance.
(b) it is obtained from wood pulp.
(c) Its fibers can also be woven like natural fibers.
Answer: The answer is (b) it is obtained from wood.
Read More: NCERT Solutions for Class 8 Science Chapter 4
Question 3. Fill in the blanks with appropriate words.
(a) Synthetic fibers are also called __________ or __________ fibers.
(b) Synthetic fibers are synthesised from the raw material called __________.
(c) Like synthetic fibers, plastic is also a __________
Answer:
(a) Synthetic fibers are also called artificial or man-made fibers.
(b) Synthetic fibers are synthesised from a raw material called petrochemicals.
(c) Like synthetic fibers, plastic is also a polymer.
Question 4. Give examples that indicate that nylon fibers are solid.
Answer:
Here are a few examples showing that nylon fibers are solid:
-
Parachutes and rock climbing ropes are made of nylon.
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Sports gear, like rackets, is also made from nylon.
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Nylon is used for seat belts, fishing nets, and tire cords.
Question 5. Explain why plastic containers are preferred for storing food.
Answer: Plastic containers are popular for storing food because they are non-reactive. This means plastic does not react with the ingredients in the food, keeping it safe and fresh. This quality makes plastic an ideal material for food storage, preventing any chemical changes or contamination.
Question 6. Explain the difference between thermoplastic and thermosetting plastics.
Answer: Thermosetting plastics harden permanently when heated, while thermoplastics can be melted and reshaped multiple times. The table below shows the further differences between them:
Thermosetting plastics |
Thermoplastics |
Thermosetting plastics break if you try to bend them |
Thermoplastics can be bent easily. |
Heating thermosetting plastics does not soften them; they cannot be reshaped after moulding. |
Heating thermoplastics softens them, allowing them to be moulded and reshaped easily. |
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Question 7. Explain why the following are made of thermosetting plastics:.
(a) Saucepan handles
(b) Electric plugs/switches/plug boards
Answer:
a) Thermosetting plastics are used for saucepan handles because they don’t conduct heat or soften when heated.
b) Bakelite is a thermosetting plastic that doesn’t conduct heat or electricity, so it’s used for making electric plugs, switches, and plug boards.8. Categorise the materials of the following products into ‘can be recycled’ and ‘cannot be recycled’.
Question 8. Telephone instruments, plastic toys, cooker handles, carry bags, ballpoint pens, plastic bowls, plastic covering on electrical wires, plastic chairs, electrical switches
Answer: The table below describes the materials that can be recycled and those that cannot be recycled.
Can be Recycled |
Cannot be Recycled |
Plastic chairs |
Cooker handles |
Plastic bowls |
Electrical switches |
Plastic toys |
Telephone instruments |
Plastic covering on wires |
Question 9. Rana wants to buy shirts for summer. Should he buy cotton shirts or shirts made from synthetic material? Advise Rana, giving your reason.
Answer: Rana should buy a cotton shirt for summer instead of a synthetic one. Cotton absorbs water well, so it soaks up sweat and helps it evaporate, cooling the body.
Question 10. Give examples to show that plastics are non-corrosive.
Answer: Plastics don’t corrode and don’t react with solid chemicals. That’s why cleaning chemicals are stored in plastic bottles instead of metal containers.
Question 11. Should the handle and bristles of a toothbrush be made of the same material? Explain your answer.
Answer: The handle and bristles of a toothbrush should be made of different materials because the handle needs to be hard and strong, while the bristles should be soft and flexible.
Question 12. ‘Avoid plastics as far as possible’. Comment on this advice.
Answer: We should not use plastics because they don’t break down naturally, causing pollution when thrown away. Burning plastics releases harmful gases, and animals can eat plastic bags, making them sick or even causing death.
Question 13. Match the terms of column A correctly with the phrases given in column B
A |
B |
(i) Polyester |
(a) Prepared by using wood pulp |
(ii) Teflon |
(b) Used for making parachutes and stockings |
(iii) Rayon |
(c) Used to make non-stick cookware |
(iv) Nylon |
(d) Fabrics do not wrinkle easily |
Answers:
A |
B |
(i) Polyester |
(d) Fabrics do not wrinkle easily |
(ii) Teflon |
(c) Used to make non-stick cookware |
(iii) Rayon |
(a) Prepared by using wood pulp |
(iv) Nylon |
(b) Used for making parachutes and stockings |
Question 14. ‘Manufacturing synthetic fibers is helping conserve forests’. Comment.
Answer: Making synthetic fibers helps protect forests because using natural fibers means cutting down many trees for their raw materials. So, using synthetic fibers helps save trees and conserve forests.
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Question 15. Describe an activity to show that thermoplastic is a poor conductor of electricity
Answer:
To demonstrate that thermoplastic is a poor conductor of electricity, we need a bulb, wires, a battery, metal, and a plastic pipe.
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In the experiment, the bulb glows when the circuit is set with the metal conductor because metal is a good conductor.
-
However, when the plastic pipe (thermoplastic) replaces the metal, the bulb does not glow, showing that thermoplastic is a poor conductor of electricity.
Science Class 8 Chapter 3 Question Answer Summary
In Class 8 Science, Chapter 3 is about synthetic fibers and plastics, which are materials used in many everyday products.
Synthetic fibers are man-made fibers created in factories. Unlike natural fibers like cotton or wool, synthetic fibers are made from chemicals. Common synthetic fibers include nylon, polyester, and acrylic. These fibers are used to make clothes, carpets, and even parts of cars. They are popular because they are strong, durable, and often cheaper than natural fibers. However, synthetic fibers do not decompose easily and can cause environmental problems when they are discarded.
Plastics are another type of synthetic material made from chemicals. They come in many forms and are used in countless items, from bottles and bags to toys and containers. Plastics are versatile and can be molded into different shapes. However, just like synthetic fibers, plastics do not break down quickly in the environment. This can lead to pollution and harm wildlife.
The chapter also discusses the advantages and disadvantages of synthetic fibers and plastics. They are useful because they are often inexpensive and last a long time. However, their environmental impact is a big concern. It is important to recycle and manage these materials properly to reduce their negative effects on the environment.
Understanding synthetic fibers and plastics helps us make better choices about using and disposing of these materials to protect our planet.
Class 8 Science Chapter 3 Question Answer FAQs
Q1. What is the name of chapter 3 in class 8 NCERT Science?
Ans. The name of chapter 3 in class 8 NCERT Geography is Synthetic Fibers and Plastics.
Q2. What are synthetic fibers?
Ans. Synthetic fibers are man-made fibers, and it is made only from polymers found in natural gas and the by-products of petroleum.
Q3. How is plastic useful in the healthcare industry?
Ans. In healthcare industry, plastics are used for packaging of tablets, as threads for stitching wounds, in syringes, doctor gloves, and for making a number of medical instruments.
Q4. What are 5 synthetic fibers?
Ans. The 5 examples of Synthetic Fibers are Polyester, Rayon, Spandex, Acrylic Fibers, and Microfibers.
Q5. What is the strongest fibre called?
Ans. Nylon is the strongest fiber amng all the fibers. It is fully a synthetic fiber.