GCSE Chemistry revision

Test for carbon dioxide

Identification of common gases

AQA 4.8.2.3 Foundation & Higher

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To test for carbon dioxide, the gas sample is bubbled through an aqueous solution of calcium hydroxide, known as limewater.
If carbon dioxide is present, the limewater turns cloudy (milky white).
The cloudiness occurs because carbon dioxide reacts with calcium hydroxide to form calcium carbonate (a solid) and water, and the solid particles make the solution appear cloudy.
The word equation for this reaction is: carbon dioxide + calcium hydroxide calcium carbonate + water.

1. Testing for Carbon Dioxide AQA

To test for carbon dioxide, the gas sample is bubbled through an aqueous solution of calcium hydroxide, known as limewater.
If carbon dioxide is present, the limewater turns cloudy (milky white).
The cloudiness occurs because carbon dioxide reacts with calcium hydroxide to form calcium carbonate (a solid) and water, and the solid particles make the solution appear cloudy.
The word equation for this reaction is: carbon dioxide + calcium hydroxide calcium carbonate + water.