NCERT Solutions | Class 8 Science Chapter 3 | Synthetic Fibres and Plastics

CBSE Solutions | Science Class 8

Check the below NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibres and Plastics Pdf free download. NCERT Solutions Class 8 Science were prepared based on the latest exam pattern. We have Provided Synthetic Fibres and Plastics Class 8 Science NCERT Solutions to help students understand the concept very well.

NCERT | Class 8 Science

NCERT Solutions Class 8 Science
Book:	National Council of Educational Research and Training (NCERT)
Board:	Central Board of Secondary Education (CBSE)
Class:	8th
Subject:	Science
Chapter:	3
Chapters Name:	Synthetic Fibres and Plastics
Medium:	English

Synthetic Fibres and Plastics | Class 8 Science | NCERT Books Solutions

You can refer to MCQ Questions for Class 8 Science Chapter 3 Synthetic Fibres and Plastics to revise the concepts in the syllabus effectively and improve your chances of securing high marks in your board exams.

NCERT TEXTBOOK EXERCISES

science class 8 pdf, Question 1.

Explain why some fibres are called synthetic.

ncert class 8 science Chapter 3 question answer, Answer :

Since man-made fibres are synthesised from petrochemicals, they are called synthetic fibres.

cbse class 8 science book, Question 2.

Mark the correct answer.
Rayon is different from synthetic fibres because
(a) it has a silk-like appearance
(b) it is obtained from wood pulp
(c) its fibres can also be woven like those of natural fibres

cbse science class 8 solutions, Answer :

(b) It is obtained from wood pulp.

cbse class 8 science Chapter 3, Question 3.

Fill in the blanks with appropriate words:

Synthetic fibres are also called…………. or……………fibres.
Synthetic fibres are synthesised from raw material called………..
Like synthetic fibres, plastic is also a …………..

ncert class 8 science Chapter 3 question answer, Answer :

artificial, man-made.
petrochemicals.
polymer.

cbse class 8 science notes pdf, Question 4.

Give examples which indicate that nylon fibres are very strong.

cbse science class 8 solutions, Answer :

They are used to make parachutes, and ropes for rock climbing.

cbse class 8 science syllabus pdf, Question 5.

Explain why plastic containers are favoured for storing food.

ncert class 8 science Chapter 3 question answer, Answer :

Three main advantages of using plastic containers for storing food are:

They do not react with food items.
They do not get rusted.
They are light, strong and durable.

cbse science class 8 book, Question 6.

Explain the difference between thermoplastic and thermosetting plastics.

cbse science class 8 solutions, Answer :

Thermoplastics can be softened on heating and can be bent easily whereas thermosetting plastics cannot be softened on heating and breaks when forced to bend.

cbse science class 8 book pdf, Question 7.

Explain why the following are made of thermosetting plastics.
(1) Saucepan handles
(2) Electric plugs Iswitches /plugboards.

ncert class 8 science Chapter 3 question answer, Answer :

The above articles are made up of bakelite (a thermosetting plastic) because it is—

the bad conductor of heat.
poor conductor of electricity.

cbse science class 8 Chapter 3, Question 8.

Categorise the materials of the following products into ‘can be recycled’ and ‘cannot be recycled’:
Telephone instruments, plastic toys, cooker handles, carry bags, ballpoint pens, plastic bowls, plastic covering on electrical wires, plastic chairs, electrical switches.

cbse science class 8 solutions, Answer :

Can be recycled	Cannot be recycled
Toys carry bags, plastic bowls, electric wire covering, plastic chairs.	Telephone instruments, cooker handles, ballpoint pens, electrical switches.

cbse science class 8 syllabus, 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.

ncert class 8 science Chapter 3 question answer, Answer :

I would advise Rana to buy cotton shirts as cotton shirts absorb the sweat and thus endorse cooling. Besides, they also provide aeration.

class 8 science Chapter 3, Question 10.

Give examples to show that plastics are noncorrosive in nature.

cbse science class 8 solutions, Answer :

It does not react with the chemical or other items stored in the containers made of it.
It does not get rusted when exposed to moisture and air.
It does not decompose when left in open for a long period.

NCERT Class 8 Science book, Question 11.

Should the handle and bristles of a toothbrush be made of the same material? Explain your answer.

ncert class 8 science Chapter 3 question answer, Answer :

The handles and bristles of a toothbrush should be made of a material which has lightweight good strength and is hygiene. “But the bristles should be soft enough so that ” they do not harm gums while the handle should be quite stiff so that it may not get bent while brushing.

NCERT Class 8 Science book PDF, Question 12.

‘Avoid plastics as far as possible.’ Comment on this advice.

cbse science class 8 solutions, Answer :

Since plastic takes several years to decompose, it is not environment friendly. It causes environmental pollution. Besides, when the synthetic material is burnt it takes a long time to get completely burnt. In the process, it releases a lot of poisonous fumes into the atmosphere causing air pollution.

ncert class 8 science Chapter 3, Question 13.

Match the terms of Column A correctly with the phrases given in Column B.

Column A	Column 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 cookwares
(iv) Nylon	(d) Fabrics do not wrinkle easily

ncert class 8 science Chapter 3 question answer, Answer :

Column A	Column B
(i) Polyester	(d) Fabrics do not wrinkle easily
(ii) Teflon	(c) Used to make non-stick cookwares
(iii) Rayon	(a) Prepared by using wood pulp
(iv) Nylon	(b) Used for making parachutes and stockings

ncert class 8 science Chapter 3 notes, Question 14.

‘Manufacturing synthetic fibres are actually helping conservation of forests. ’ Comment.

cbse science class 8 solutions, Answer :

The synthetic fibres are made up of petrochemicals. So, manufacturing synthetic fibres does not depend upon plants. These synthetic fibres cater to the need of people up to great extent. Thus, the forests are not destroyed to manufacture clothes and other items. So, indirectly, we can come to the conclusion that manufacturing synthetic fibres is actually helping the conservation of forests.

NCERT Science book Class 8 Solutions PDF free download, Question 15.

Describe an activity to show that thermoplastic is a poor conductor of electricity.

ncert class 8 science Chapter 3 question answer, Answer :

A thermoplastic (or plastic) is a poor conductor of electricity as shown in Fig. 3.3.
If we place a piece of copper in the gap touching points A and B (in Fig. 3.3), we observe that bulb glow. If we place plastic in the gap between A and B, we observe that the bulb will not glow. It means plastic is a poor conductor.