Identifying Gases: Tests and Results

The video tutorial explains how to identify four different gases: hydrogen, oxygen, carbon dioxide, and chlorine. For hydrogen, a burning splint is used, which causes a squeaky pop if hydrogen is present. Oxygen is tested with a glowing splint that relights in its presence. Carbon dioxide is identified by its reaction with limewater, turning it cloudy. Chlorine is detected by its ability to bleach damp litmus paper.

What is the expected result when a burning splint is used to test for hydrogen gas?

• The gas turns the splint black.

• The splint relights.

• The gas explodes with a squeaky pop sound.

• The splint extinguishes.

Why is the test tube held upside down when testing for hydrogen?

• Because hydrogen is denser than air.

• To prevent the gas from escaping.

• Because hydrogen is less dense than air.

• To allow the gas to mix with air.

What happens when a glowing splint is inserted into a test tube containing oxygen?

• The splint relights.

• The splint extinguishes.

• The gas explodes.

• The gas turns the splint black.

How can you test for the presence of carbon dioxide using limewater?

• The limewater remains clear.

• The limewater turns blue.

• The limewater turns red.

• The limewater turns cloudy.

What is the effect of chlorine gas on damp litmus paper?

• The paper turns white.

• The paper turns blue.

• The paper turns red.

• The paper remains unchanged.