1. Summary of Tests for Gases

2. Positive Test Indicator
Gas
Name of Test
Positive Test Indicator
Oxygen
Glowing Splint
Glowing splint bursts into flame
Hydrogen
Burning Splint
Burning splint produces a loud pop sound
Carbon Dioxide
Extinguished Flame
Burning splint is extinguished
Limewater
Cloudy white precipitate forms out of the limewater
Water Vapour
Cobalt Chloride Paper
Test paper turns from blue to pink

3. Order of Tests for an Unknown Gas
Step 1. Glowing Splint
Splint bursts into flame: Oxygen
No change: ……………….Go to step 2
Step 2. Burning Splint
Produces a loud ‘pop’ sound: Hydrogen
Flame is extinguished:……. Go to step 3
No change:……………. Go to step 4

4. Produces a cloudy precipitate: Carbon Dioxide Step 4. Cobalt Chloride
Step 3. Limewater
Produces a cloudy precipitate: Carbon Dioxide
Step 4. Cobalt Chloride
Paper turns from blue to pink: Water Vapour