A quality-control technician sends a carbon dioxide sample along a delivery tube into limewater. The end of the tube is below the surface, but the tube has a crack above the liquid. After the sample has flowed for a short time, the limewater remains clear. Why could the crack cause this result?
The carbon dioxide loses the pressure needed to react with the limewater at the crack.
The crack makes the carbon dioxide bubbles too large for the limewater to turn cloudy.
Most of the carbon dioxide escapes through the crack, so too few bubbles pass through the limewater.
The carbon dioxide must be trapped above the limewater before the solution can turn cloudy.
89 exam-style questions on AQA GCSE Chemistry 8.2 Identification of common gases, covering 8.2.1 Test for hydrogen, 8.2.2 Test for oxygen, 8.2.3 Test for carbon dioxide, and 8.2.4 Test for chlorine. Each one has a worked solution and a mark scheme showing where the marks go.