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Key points

  • Nitrogen is an . It's a at room temperature.

  • Nitrogen makes up about 78% of the Earth's atmosphere.

  • Liquid nitrogen is very cold, so it is often used to freeze food.

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What is nitrogen?

A short video explaining where nitrogen can be found and used.

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How is nitrogen used?

Nitrogen has just one type of , so it is an element. It's found naturally as a , each containing two nitrogen atoms. This gives it a chemical formula of 狈鈧. Nitrogen has a low and and is a gas at room temperature.

The Earth鈥檚 is made up of 78% nitrogen. The next most common gas is oxygen, at 21%. Nitrogen isn't very reactive, but it can react with oxygen at high temperatures, such as in car engines. These reactions make nitrogen oxides.

The boiling point of nitrogen is 鈭196 掳C, so liquid nitrogen is very cold indeed. This means liquid nitrogen is ideal for freezing food, such as vegetables, very quickly, allowing them to stay fresher for longer.

A rotating model of a nitrogen molecule.

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Play the Atomic Labs game! game

Try out practical experiments in this KS3 science game.

Play the Atomic Labs game!
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More on Atoms, elements and compounds

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