Page 51 - FOUNDATIONS FOR LIFE; EXPLORING GOD’S UNIVERSE

Science - Y5 – God’s Amazing Matters – week 9

Read the following information about plastics then answer the questions.

Properties of plastic
Plastics are: - a) mouldable
b) transparent, translucent or opaque
c) tough
d) good heat and electrical insulators
e) many plastics melt at relatively low temperatures
f) their texture, colour and hardness can easily be changed
g) lightweight
h) not as strong as metals
i) fairly resistant to chemicals
j) mix easily with pigments to change colour

How plastic is made
There are many kinds of plastic. They are made up of polymers which are substances consisting of
many identical building blocks. Plastics are formed from chemical reactions. They arrive at the
factory as pellets which are mixed with other substances to change the colour and properties then
heated to a liquid form before being shaped.

Polythene is built on a single chain of carbon and hydrogen bonded together.
Polystyrene is a form of plastic made from ethylene and benzene gases.

Recycling plastics
They are all different so are more challenging to recycle. Some can be burned to give energy for
power plants. Some can be used for other purposes.

1. Why are electric wires covered in plastic? ________________________________________

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2. What are polymers? __________________________________________________________

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3. What is the difference between polythene and polystyrene? ____________________________

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4. Why are plastics difficult to recycle? ______________________________________________

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