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The atmosphere and the environmentTests for gases

The composition of the atmosphere has changed since the Earth was formed 4.5 billion years ago. Natural processes and human activity have changed the atmosphere, and continue to change it today.

Part of Chemistry (Single Science)The ever changing world

Tests for gases

Hydrogen, oxygen and carbon dioxide can be identified using different tests.

Hydrogen

Putting the flame of a lighted wooden splint in a test tube of hydrogen makes a 鈥榮queaky pop鈥 sound.

Oxygen

Putting a glowing wooden splint in a test tube of oxygen, causing the splint to relight.

Carbon dioxide

Bubbling carbon dioxide through changes it from colourless to 鈥榤ilky鈥 due to the formation of a white precipitate of calcium carbonate.

Diagrams showing how to test for three gases: hydrogen, carbon dioxide and oxygen.

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