Category Chemistry

Many metals, such as iron and steel, are strong and heavy. They are used to make machines or buildings. There is also a need for metals that are strong and light. A car needs to be strong, but it uses up less petrol if it is also light.

Aircraft need to be strong and light.

A light aircraft is cheaper to fly than a heavy one because it uses less fuel. It is also faster. But aircraft must be strong too. Titanium is as strong as steel but nearly half as light! This aeroplane is made mainly out of the metals titanium and aluminium.

This metal was worth more than gold!

Aluminium used to be more valuable than gold! It was precious because it was hard to find and costly to make. Today, it is much cheaper and is used to make cans and kitchen foil.

There is metal in your body.

Inside your body, there are tiny natural traces of metal such as iron and zinc. These are not chunks of solid iron. Instead, these metals flow around your body in your blood. Metals in the body are called minerals. We get them from eating different foods.

You can see and touch metals used in things like drink cans and bikes. Metals also make it possible for you to switch on a light. Your computer uses metals to work and there is even metal in the paint on your walls.

Electricity flows easily through some metals.

Electricity only flows easily through some materials. It cannot flow through wood or plastic. But it can flow through some metals, such as copper. These metals are called conductors. Many electrical wires are made from copper. Without metals, we could not use electricity as we do today.

What would happen if you had a wooden saucepan?

Many materials catch fire easily. A wooden saucepan would burn if it was heated. A metal saucepan gets hot but does not melt. Metal is a good conductor of heat. It lets heat through, but doesn’t burn unless it is extremely hot.

Mercury is a runny metal.

Mercury is the only metal that stays as a liquid at room temperature. This silver-coloured metal used to be called quicksilver because of the way it runs and flows. Mercury changes shape when it heats up or cools down. Because of this it can be used in thermometers to measure temperature.

Gold, silver and platinum are special metals. They are used to make necklaces and bracelets. These metals cost a lot of money because they are hard to find. Precious metals are very important because they have other uses – they are even used in space.

Gold was once used as money.

Rare metals are often called precious metals. They are worth a lot of money. Gold is only found in a few rocks, although in some parts of the world, you may be lucky and find a nugget of gold in some river mud! Gold and silver sparkle and shine. Platinum is a beautiful silver-white colour. It is very tough.

Continue reading “Metals – Shiny and gold!”

Much of the metal we use has been used before. You can use metals again and again, by melting them down and making new things from them. This is called recycling. Recycling is very important.

Recycling saves energy.

Taking metal from rocks in the ground is expensive and uses up lots of energy. It creates pollution when the rocks are shipped across the world in trucks and boats. Each year, we use so many aluminium cans that if you stacked them, they could reach to the Moon and back! You can make twenty recycled cans with the same energy needed to make just one new can.

A magnet sorts out different metals.

Machines chew up the old bits of metal in washing machines, cars and cans. The machine squeezes out small clean pieces of metal. A huge magnet separates iron and steel. Each type of metal is melted down and used again.

You can sort out different metals.

Some metals are magnetic. This means they will be pulled towards a magnet. Iron and steel are magnetic. Copper and brass are not. With a small magnet, try to pick up a selection of metal objects. Which ones are magnetic?

We use metals every day. Our lives would be very different without metals. Scientists are always finding amazing new ways to use metals. They look for new places to dig for metals and for new metal materials to make.

There are metals at the bottom of the sea!

It is expensive to dig deep below the sea but it may cause less pollution and damage to the area than mining on land. Some scientists are looking into ways of using tiny creatures called bacteria to collect the metals from the sea!

Metal blankets keep out flames.

Using aluminium and other metals in blankets keeps in heat and keeps out flames. These thermal blankets are used in space to keep astronauts warm, and here on Earth to protect climbers on cold, snowy mountains.

There are metals in space!

High above the sky, metals are found in shining stars, on other planets and in huge pieces of rock that float around in space. If humans ever build on another planet, may be they could use the supply of metal from outer space.

Metals are strong, but they can be made into many shapes. There are lots of ways to shape metal. Most metals can be bent and pulled when they are very hot. A few metals, such as copper, lead and gold, can be shaped even when they are cold.

Copper is pulled into thin wires.

Hot runny metal can be poured into a mould to set, like a jelly – but the cold metal will not wobble! Hot steel is squashed in huge rollers. Gold and silver can be hammered into sheets as thin as paper. Copper is stretched into thin tube shapes to be used for wires. Copper and gold do not have to be heated before they are shaped.

Continue reading “Metal Bend and stretch”