Which of the following is a source of rayon?

1

(a)

Wool

(b)

PET

(c)

Wood pulp

(d)

Silk

Polycot is obtained by mixing

1

(a)

nylon and wool

(b)

polyester and wool

(c)

nylon and cotton

(d)

polyester and cotton

PET is a

1

(a)

polyester

(b)

nylon

(c)

polyamide

(d)

thermosetting polymer

Which is not made from nylon?

1

(a)

socks

(b)

rope

(c)

bottles

(d)

tents

The strongest fibre is called:

1

(a)

rayon

(b)

nylon

(c)

acrylic

(d)

none of these

A plastic used for making crockery is.........

1

(a)

melamine

Plastics are............ conductors of heat

1

(a)

poor

_________ is quite suitable for making dress material.

1

(a)

Terylene

__________ and ________ are some of the examples of thermoplastics.

1

(a)

Polythene, PVC

Plastic does not react with ________ and ________.

1

(a)

moisture, air

Artificial fibres are stronger than natural fibres.

1

(a) False

(b) True

Electric switches, plugs, sockets and handles of cooking utensils are made up of thermoplastics.

1

(a) True

(b) False

PVC is thermosetting plastic.

1

(a) True

(b) False

Rayon is the fully synthetic fibre.

1

(a) True

(b) False

We should not wear synthetic clothes while cooking in the kitchen or in a laboratory.

1

(a) False

(b) True

Which is biodegradable? Paper bag or polythene bag?

2

(a)

Paper bag.

What are natural fibres?

2

(a)

The fibres obtained from nature are called natural fibres e.g., cotton.

Name any two thermoplastic and thermosetting plastics.

2

(a)

(i) Thermoplastic - Polythene, PVC
(ii) Thermosetting plastics - Melamine, Bakelite.

Name the articles made from PET.

2

(a)

Bottles, utensils, films, wires etc.

What is the versatility about melamine?

2

(a)

It resists fire and can tolerate heat better than plastic.

Write the name of raw materials which are used in making nylon.

2

(a)

The manufacture of which artificial fibres contributes to deforestation?

2

(a)

Why does plastic find such variety of uses?

2

(a)

When we add hot water in a plastic bottle, it gets deformed. What kind of plastic is it? Give two more examples.

2

(a)

"Manufacturing synthetic fibres is actually helping conservation of forests". Comment.

2

(a)

1. A bucket made up of plastic does not rust like a bucket made up of iron. Why?

   5

   (a)

2. Write disadvantages of plastics.

   5

   (a)

1. Nikita's mother went to the market to buy new lunch box for Nikita. She saw different lunch boxes made up of plastics as well as steel. Plastics lunch boxes of different colours was very attractive but the steel lunch box was very simple. Nikita's mother told him to select a lunch box for you. She selected a lunch box made of steel instead of plastic one. Her mother purchased the steel lunch box for him.
   Read te following passage and answer the following questions.
   (a) Why Nikita prefer steel lunch box instead of plastic one?
   (b) Is plastic materials environment friendly? Explain.
   (c) What values are shown by Nikita?

   5

   (a)

2. Shruti's mother went to the market to buy new lunch box for Shruti. She saw different lunch boxes made up of plastics as well as steel. Plastic lunch boxes of different colours were very attractive but the steel lunch box was very simple. Shruti's mother told her to select a lunch box for her. She selected a lunch box made of steel instead of plastic one. Her mother purchased the steel lunch box for her.
   Read the passage and answer the following questions:
   (i) Why does Shruti prefer steel lunch box instead of plastic one?
   (ii) Are plastic materials environment friendly? Explain.
   (iii) What values are shown by Shruti?

   5

   (a)