2.39 describe tests for the gases: i hydrogen ii oxygen iii carbon dioxide iv ammonia v chlorine.

Hydrogen: Mix with air and ignite- 'squeaky pop'

Oxygen: Insert glowing splint- splint relights

Carbon dioxide: Bubble through limewater- limewater turns milky

Ammonia: Damp red litmus paper- turns blue

Chlorine: Damp litmus paper- turns white