Metals, magnets and recycling

Ferrous and non-ferrous metals, rust, recycling, metal theft and the four R’s. Read one part at a time and tap “I know this”. Then test yourself in the quiz.

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Sorting metals

Metal	Kind	Use and why
Steel	Ferrous	Nails, beams: strong (and a magnet attracts it)
Copper	Non-ferrous	Electrical wiring: conducts well and bends easily
Aluminium	Non-ferrous	Cool-drink cans: light, rust-free, recyclable
Nickel	Non-ferrous	One of the few magnetic metals without iron

A scrap dealer sorts quickly with a magnet. Test a paper clip, copper wire, a steel nail and an aluminium can: only the paper clip and the steel nail are attracted. Metals are sorted because each melts differently and has its own value.

Tap when you could tell someone without looking.

Recycling and the four R’s

Reduce is best: less is mined, made and melted.

Example	Which R?
A family buys one big tin of paint instead of many small tins	Reduce
The school uses old tins as plant pots	Reuse
Lerato fixes the pot’s handle	Repair
Cans are crushed, melted and made into new cans	Recycle

Metal can be recycled many times without losing quality; it saves energy and leaves ore in the ground.
Theft of copper cable stops power, phones and train signals; stolen manhole covers leave dangerous holes.
A legal dealer is registered and records each seller’s ID. Take old metal to one, or to a buy-back centre.
Wood outdoors: seal with varnish, oil or paint. Canvas for a tent: treat it to make it waterproof.

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Remember this and test yourself

Remember this: your summary

Ferrous metals contain iron (steel); they rust and a magnet attracts most of them.
Non-ferrous: copper, aluminium, zinc. Usually not magnetic and do not rust.
Iron needs water and oxygen to rust. Prevent rust: paint, oil or zinc (galvanise).
Brass is an alloy of copper and zinc.
Four R’s: reduce, reuse, repair, recycle.

Write these points in your book. Read them again the night before the test.

Memory trick

Fe is iron: ferrous = iron inside, rusts and sticks to a magnet.

Flash cards · Tap to turn over

Important words

First say what the word means, then turn the card over.

Test yourself · Part 2

True or false?

Read the question and the answer. Is the answer right? Tap True or False.

Now the real quiz!

The quiz has many more questions on this topic. Every question shows straight away whether you are right and explains why.

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For parents

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