Give examples which indicate that nylon fibres are very strong.

3

(a)

Explain why plastic containers are favoured for storing food?

3

(a)

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

3

(a)

'Avoid plastics as far as possible'. Comment on this advise

3

(a)

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

3

(a)

What are the properties of nylon?

3

(a)

Plastics are poor conductors of heat and electricity. Explain by giving examples.

3

(a)

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

3

(a)

What are the disadvantages of synthetic fibres?

3

(a)

Take two cloth pieces of the same size, one from natural fibre and another from synthetic fibre. Soak them in different mugs containing same amount of water. After five minutes spread them in the Sun. Observe and answer the following:
(i) How much water is soaked by both fibres?
(ii) Which fibre soaks more water?
(iii) Which fibre dries quickly?

3

(a)

Why do plastic containers seem most convenient?

3

(a)

How can we say that plastic is non-reactive?

3

(a)

Write any three positive characteristics of plastic.

3

(a)

What is 4R principle?

3

(a)

Write disadvantages of plastics.

3

(a)