chemial analysis - testing for gases

Question 1

how do we test for hydrogen?

Answer 1

we remove the bung and insert a burning splint. hydrogen gas burns rapidly and produces a pop sound

Question 2

how do we test for oxygen?

Answer 2

use a glowing splint. place glowing splint in tube of oxygen which will relight if oxygen present

Question 3

how do we test for carbon dioxide?

Answer 3

use limewater. limewater is an aqueous solution of calcium hydroxide. draw some of the gas (co2) into a pipette and bubble the gas through the limewater. repeat several times, limewater may turn cloudy showing gas was carbon dioxide

Question 4

how do we test for chlorine?

Answer 4

we insert damp litmus paper into the mouth if the test tube. chlorine bleaches the litmus paper turning it white