What is the positive result when testing for oxygen gas?

• The splint burns with a pop sound.

• The limewater turns milky.

• A glowing splint relights.

• A burning splint relights.

What sound indicates the presence of hydrogen gas during a test?

• A hissing sound.

• A loud bang.

• A pop sound.

• No sound.

What happens to limewater when carbon dioxide gas is bubbled through it?

• It turns red.

• It becomes colorless.

• It turns milky.

• It produces a pop sound.

What is the expected observation when damp blue litmus paper is exposed to chlorine gas?

• It turns red and then bleaches white.

• It remains blue.

• It turns green.

• It immediately bleaches white without turning red.