Testing for Hydrogen, Oxygen, Carbon Dioxide, Ammonia and Chlorine

The video tutorial explains how to test for the presence of various gases in the laboratory, including hydrogen, oxygen, carbon dioxide, ammonia, and chlorine. Each gas has specific tests: hydrogen produces a squeaky pop with a lit splint, oxygen relights a glowing splint, carbon dioxide turns lime water milky, ammonia turns red litmus paper blue and forms white smoke with hydrochloric acid, and chlorine bleaches blue litmus paper. The tutorial emphasizes the importance of these tests due to the colorless and odorless nature of many gases.

Why is it necessary to test gases in the laboratory?

• Because gases are always odorous.

• Because gases cannot be identified by appearance alone.

• Because gases are always visible.

• Because gases have distinct colors.

What sound is produced when hydrogen is tested with a lit splint?

• A loud bang

• No sound

• A squeaky pop

• A hissing sound

What happens to a glowing splint in the presence of oxygen?

• It remains unchanged.

• It relights.

• It extinguishes.

• It changes color.

How can you confirm the presence of carbon dioxide?

• By bubbling it through lime water.

• By using a glowing splint.

• By using a lit splint.

• By using damp red litmus paper.

What color change occurs when chlorine is tested with damp blue litmus paper?

• It turns yellow and then white.

• It turns red and then black.

• It turns blue and then green.

• It turns red and then white.