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Why is hydrogen collected by upwards delivery?
It is less dense than air.
It is denser than air.
It is insoluble in water.
Why is carbon dioxide collected by downwards delivery?
Why can't ammonia be collected over water?
It is very soluble in water.
Which of these methods is the most suitable for collecting oxygen?
By upwards delivery.
By downwards delivery.
A test for the presence of ammonia is:
Limewater turns cloudy
Damp red litmus paper turns blue.
Damp blue litmus paper turns red.
A test for the presence of oxygen is:
A lighted splint goes out.
A glowing splint relights.
Limewater turns cloudy.
A test for the presence of chlorine is:
Damp starch iodide paper turns blue-black.
White clouds form in the presence of concentrated hydrochloric acid.
A lighted wooden splint makes a popping sound in a test tube of gas. The gas is most likely to be: