Class 8 Science Chapter 3 MCQ

Class 8 Science Chapter 3 MCQ (Multiple Choice Questions) of Synthetic Fibres and Plastic. A full revision with question-answer and explanation in the form of MCQs based on latest CBSE Syllabus for new academic session 2020-2021.

After selecting the correct or incorrect answers, you can see the right answers with reason behind them.

Class 8 Science Chapter 3 MCQ for 2020-2021

Class: 8Science
Contents:Multiple Choice Questions – MCQ Tests

Class 8 Science Chapter 3 MCQ for Exams

Class 8 Science Chapter 3 MCQ with complete explanation are given below. There more than 100 questions with answers based on Class 8 Science Chapter 3 NCERT Textbook. All the 20 sets of online tests are free to use again and again. If you feel revision, please visit to Important Questions or NCERT Solutions links given just below to each question.

Q1

Paheli is writing some statements. She wants to know in which of the following statements is or are incorrect?

[A]. The fabric terry wool is obtained by mixing terylene and wool.
[B]. It is risky to wear synthetic clothes while working in the kitchen.
[C]. Some of the plastics are biodegradable.
[D]. Synthetic fibres do not melt on heating.
Q2

Consider the following statements, choose the incorrect one:

[A]. The synthetic fibres are also known as man-made fibres.
[B]. A fibre similar to wool is acrylic.
[C]. A monomer is a chain of many small units of polymer.
[D]. The first fully synthetic fibre was rayon.




Q3

Consider the following statement and choose the incorrect one:

[A]. Chemical name of natural polymer of cotton is cellulose.
[B]. Rayon is often regarded as artificial silk.
[C]. Terycot is made by mixing terylene and cotton.
[D]. None of the above
Q4

Which of the following is not a common property of plastic?

[A]. Non-reactive
[B]. Light in weight
[C]. Durable
[D]. Good conductor of electricity
Q5

The material similar to silk in appearance is:

[A]. Nylon
[B]. Rayon
[C]. Polyester
[D]. Terylene
Q6

Paheli is taking preparation for her final examination. She is writing some statements about “Nylon” but she confused to know whether the statements are correct or not? Would you help her?

[A]. Nylon is the first fully synthetic fibre.
[B]. Nylon is made up of the repeating units of amide chemical.
[C]. Nylon is a thermosetting polymer.
[D]. Nylon fibres absorb very little water.




Q7

Boojho is writing some statements about polyester. In which of the following statements is or are incorrect? Help him.

[A]. Polyester is a thermoplastic polymer.
[B]. Polyester fibres are stronger than nylon fibre.
[C]. Polyester do not stretch but rot in contact with water.
[D]. Polyester is used for making water hoses for fire-fighting operations.
Q8

Rayon is different from truly synthetic fibres because:

[A]. It has a silk like appearance.
[B]. It is obtained from wood pulp.
[C]. Its fibres can be woven like those of natural fibres.
[D]. It can be dyed in wide variety of colors.



Q9

Which of the following is a source of rayon?

[A]. Wool
[B]. PET
[C]. Wood pulp
[D]. Silk
Q10

Pick the synthetic fibre out of the following:

[A]. Cotton
[B]. Nylon
[C]. Jute
[D]. Wool

Identification of fibres by burning their threads

Cotton:Burns completely, leaving no residue.
Nylon:Burns slowly; fabric shrinks after exposure to flame, forms hard beads and gives off a smell of burning hair.
Wool and SilkBurns slowly, with a smell like that of burning hair but no beads are produced.
PolyesterResults are like nylon, except that black smoke is produced.
RayonBurns quickly with a smell of burning paper.
AcrylicBurns slowly with a sooty flame; fabric shrinks from flame, and forms black beads.



Detergent

Leftover chemical substances obtained from petroleum products were treated with sulphuric acid to invent a new soap-like product known as detergent.

What is a polymer?

A long chain of molecules is called a polymer. It is made up of a large number of monomer molecules joined end to end to form a large molecule. There are many polymers that occur naturally, such as rubber, silk, wool and even cotton.

Which is the first man made synthetic polymer?

The first man-made synthetic fibre, nylon, was put into commercial production in 1939 by a team of scientists of the famous chemical company, E.I. Dupont de Nemours. Nylon derives its name from the first letter of ‘New York’ and first three letters of ‘London’, the two cities where it was simultaneously developed and marked.

What is Rayon?

Rayon is a type of synthetic (man-made) material that resembles silk in appearance.

What are the different forms of Terylene?

Terylene has wool-like texture, which is why it is often used to weave fabrics for making suits, trousers, etc. It is called terycot when blended with cotton, and terywool when mixed with wool.