Testing for Gases

To test for Hydrogen, we remove the pung and insert a burning splint.

Hydrogen gas burns rapidly and produces a pop sound.

To test for oxygen, we use a glowing splint.

If we place the glowing splint into a test tube of oxygen, the splint relights (bursts into flames)

To test for carbon dioxide, we use limewater. (Limewater is an aqueous solution of calcium hydroxide)

Draw some of the gas into a plastic pipette.

Bubble the gas through the limewater.

If we repeat this several times, the limewater may turn cloudy.

If the limewater turns cloudy then that tells us that the gas was carbon dioxide.

To test for chlorine, we insert damp litmus paper into the mouth of the test tube.

Chlorine bleaches the litmus paper and turns it white.