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ScienceChemistry
Materials: fun facts and quiz
The essentials in 7 ideas, with fun facts, an illustrated story and a quiz to see how much you know.
The essentials
Metals & Alloys
Mixing metals makes alloys with better properties. Bronze is copper and tin; steel is iron with a little carbon, which makes it much stronger.
Key fact
The Bronze Age began over 5,000 years ago.
Glass
Glass is made by melting sand, which is mostly silica, with other ingredients, then cooling it quickly so it doesn’t form crystals.
Key fact
Glass doesn’t slowly flow: old windows were simply made uneven.
Ceramics
Ceramics like pottery, bricks and porcelain are made by firing clay at high temperatures. They’re hard and heat-resistant, but they can shatter.
Key fact
The space shuttle’s heat-shield tiles were a kind of ceramic.
Natural Materials
Wood, cotton, wool, leather and stone are natural materials. Wood is strong for its weight, so some modern buildings use engineered timber.
Key fact
Some timber towers now rise more than 80 metres.
Concrete
Concrete, a mix of cement, sand, gravel and water, is the most used building material on Earth. Steel bars inside make reinforced concrete much stronger.
Key fact
Around 30 billion tonnes of concrete are used every year.
Wonder Materials
Graphene is a sheet of carbon just one atom thick. It’s incredibly strong and flexible, and it conducts electricity. It was first isolated in 2004, using sticky tape.
Key fact
Its discoverers won the 2010 Nobel Prize in Physics.
Recycling Materials
Many materials can be recycled. Aluminium cans can be recycled again and again, using far less energy than making new metal.
Key fact
Recycling aluminium saves about 95% of the energy.
Fun facts
Pure gold is so soft you can dent it with a fingernail, so jewellery gold is usually mixed with other metals.
When lightning strikes sand, it can melt it into hollow glass tubes called fulgurites.
Fine porcelain is called “china” in English because it first came from China.
Weight for weight, spider silk is stronger than steel.
The Hoover Dam’s concrete was cooled with pipes of chilled water. Left alone, it would have taken over a century to cool.
Graphene is astonishingly light: a whole square metre of it weighs less than a milligram.
Recycled cans can be back on the shelf, as new cans, in about 60 days.
Story: Fire on the Beach
Fire on the Beach
The Roman writer Pliny tells a legend: traders once camped on a sandy beach and propped their cooking pots on blocks of soda.
In the heat of the fire, the soda and sand melted together, and a strange, clear liquid trickled out.
Glass, or so the story goes. In fact people made glass in Mesopotamia over 4,000 years ago, long before Pliny.
True or false?
Tap your answer to see if you got it, and why.
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Question 1 of 10
Steel is mostly iron.
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True. With a small amount of carbon.
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Question 2 of 10
Glass is made mainly from sand.
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True. Mostly silica, melted at very high temperatures.
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Question 3 of 10
Bricks are a type of ceramic.
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True. Fired clay.
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Question 4 of 10
Wool is a natural material.
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True. It comes from sheep.
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Question 5 of 10
Concrete is the world’s most used building material.
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True. By a long way.
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Question 6 of 10
Graphene is one atom thick.
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True. A single layer of carbon atoms.
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Question 7 of 10
Aluminium can be recycled many times.
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True. Without losing quality.
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Question 8 of 10
Bronze is made from iron and gold.
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False. It’s copper and tin.
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Question 9 of 10
Old church windows sag because glass slowly flows.
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False. They were made unevenly; glass doesn’t flow at room temperature.
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Question 10 of 10
Ceramics melt at low temperatures.
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False. They survive very high heat.
Keep going in the app
KnowSoda learns what you know and brings back what you’re about to forget. Materials has 6 more ideas at the Advanced and Expert levels.
