Test: Synthetic Fibres And Plastics - 4


20 Questions MCQ Test Science Class 8 | Test: Synthetic Fibres And Plastics - 4


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This mock test of Test: Synthetic Fibres And Plastics - 4 for Class 8 helps you for every Class 8 entrance exam. This contains 20 Multiple Choice Questions for Class 8 Test: Synthetic Fibres And Plastics - 4 (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Synthetic Fibres And Plastics - 4 quiz give you a good mix of easy questions and tough questions. Class 8 students definitely take this Test: Synthetic Fibres And Plastics - 4 exercise for a better result in the exam. You can find other Test: Synthetic Fibres And Plastics - 4 extra questions, long questions & short questions for Class 8 on EduRev as well by searching above.
QUESTION: 1

Fabric is made of

Solution: As for making cotton cloth we turn it into yarn to make cloth so for that we need cotton so for fabric we need fibre.
QUESTION: 2

The small units used in making synthetic fibres are:

Solution:

A polymer is a substance or material consisting of very large molecules, or macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life.

QUESTION: 3

The strongest fibre is called:

Solution: Its answer is nylon because it is the first fully synthetic fibre made by using cool air and water it is strong as nylon rope is used for parachutes and rock climbing also a nylon thread is much stronger than a steel wire.
QUESTION: 4

The first man-made fibre is

Solution:

The first fully synthetic fibre, nylon, is a man-made fibre. Back in 1931, it was made purely from coal, water, and air. It did not use raw materials from animals and plants.

QUESTION: 5

The plastics which do not remould again on heating are called:

Solution:

The plastics which cannot be remoulded again on heating are called thermosetting plastics. The most common examples of thermosets are Bakelite and Melamine.

QUESTION: 6

The polyester is made up of

Solution:

Polyester is a synthetic polymer made of purified terephthalic acid (PTA) or its dimethyl ester dimethyl terephthalate (DMT) and monoethylene glycol (MEG). With 18% market share of all plastic materials produced, it ranges third after polyethylene (33.5%) and polypropylene (19.5%).

QUESTION: 7

The nylon is prepared first in

Solution:

Nylon is another man-made fibre. In 1931, it was made without using any natural raw material (from plant or animal). It was prepared from coal, water and air. It was the first fully synthetic fibre. Nylon fibre was strong, elastic and light. It was lustrous and easy to wash. So, it became very popular for making clothes. We use many articles made from nylon, such as socks, ropes, tents, toothbrushes, car seat belts, sleeping bags, curtains etc.

QUESTION: 8

The fibre made up by the chemical treatment of wood pulp is

Solution:
QUESTION: 9

A synthetic fibre which works like wool.

Solution:

The correct answer is C as A synthetic fibre which works like wool is ACRYLIC

QUESTION: 10

The raw materials used in making nylon

Solution:
QUESTION: 11

 Polyester is a natural fibre. 

Solution:
QUESTION: 12

Cotton is the polymer of cellulose.

Solution:

Cotton, like rayon and wood pulp fibers, is made of cellulose. Cellulose is a macromolecule made up of anhydroglucose unit connected by 1, 4 oxygen bridges with the polymer repeating unit being anhydro-beta-cellulose.

QUESTION: 13

We should use more and more polythene bags.

Solution:

It takes 1000 years for polythene bags to degrade. Polythene bags don't Biodegrade, they photo - degrade, breaking down into smaller and smaller toxic bits contaminating soil and waterways. It pollutes our environment.
So, we should not use polythene bags.

QUESTION: 14

Silk is the most expensive natural fibre. 

Solution:
QUESTION: 15

We get natural fibres from plants and animals.

Solution:
QUESTION: 16

 Acrylic is a synthetic fibre which works like wool.

Solution:
QUESTION: 17

Nylon was made first in 1931.

Solution:
QUESTION: 18

Rayon was prepared by coal, water and air.

Solution:
QUESTION: 19

Cotton and jute are the two common synthetic fibres.

Solution:

"Cotton and jute” are the two common natural fibres not synthetic fibres.

QUESTION: 20

PVC is a thermosetting plastic.

Solution:

PVC is a thermoplastic. Thermosetting plastics are crosslinking plastics that require a chemical reaction to cause them to harden. Epoxies and urethanes are two common examples of thermosetting plastics.

Thermoplastics harden by cooling. The plastic beads are melted by heat using mechanical means in an extrusion screw. Unless the thermoplastic is ruined by over heating, it can be reused many times. Unlike a thermosetting plastic that once the two chemicals have been mixed causing the reaction cannot be reused in the same way. They may become fillers but not have the same properties.