Testing for Gases

Why do we need laboratory tests for gases?

• Because we can't see them

• Because they are colourless and odourless

• To prove we are right

Describe how to test for carbon dioxide

• Hold damp litmus paper need the gas

• Insert a glowing splint into the tube of the gas

• Bubble some of the gas through limewater

• Insert a lit splint into a tube of the gas

What will the positive result be for carbon dioxide?

• The litmus paper will be bleached white

• The glowing splint will relight

• The limewater will go cloudy

• The gas will burn with a squeaky pop

Describe how to test for hydrogen

• Hold damp litmus paper need the gas

• Insert a glowing splint into the tube of the gas

• Bubble some of the gas through limewater

• Insert a lit splint into a tube of the gas

What will the positive result be for hydrogen?

• The litmus paper will be bleached white

• The glowing splint will relight

• The limewater will go cloudy

• The gas will burn with a squeaky pop

What paper is needed to test for chlorine?

• Damp litmus paper

• Universal indicator paper

• Filter paper

• Chromatography paper

A glowing splint relights when placed near a gas. Which gas is it?

• Chlorine

• Oxygen

• Carbon dioxide

• Hydrogen