Preparing and Testing gases

Question 1

Test for chlorine?

Answer 1

Bleaches damp litmus paper - turning it white

Question 2

Test for oxygen?

Answer 2

Relights a glowing splint

Question 3

Test for carbon dioxide?

Answer 3

Turns limewater cloudy

Question 4

Test for hydrogen?

Answer 4

Makes a squeaky pop with a lighted splint

Question 5

Test for ammonia?

Answer 5

Turns damp red litmus paper blue

Question 6

Test for water?

Answer 6

Water turns white crystals of copper sulfate blue when heated

Question 7

Preparing oxygen?

Answer 7

Decomposition of hydrogen peroxide

Manganese oxide catalyst

Question 8

How to prepare carbon dioxide in the lab? (2)

Answer 8

1) dilute acid (eg hcl) reacts with calcium carbonate to produce carbon dioxide
Hydrochloric acid + calcium carbonate —> calcium chloride + water + carbon dioxide

2) thermal decomposition of metal carbonates produce co2
Eg — copper carbonate —> copper oxide + carbon dioxide