Same chapter3 marksDifficulty: Medium
State three uses of hydrogen.
Study of the First Element: Hydrogen
3 marksDifficulty: Medium
How is hydrogen collected in the laboratory and how is it tested?
Original Khojo Papers practice question — not from a past board paper.
Answer
Hydrogen is collected by the downward displacement of water, because it is almost insoluble in water and much lighter than air. It is tested by bringing a lighted splint to the mouth of the tube: the gas burns with a pale blue flame and a pop sound.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
It is not collected by the downward displacement of air because it would mix with the air and form an explosive mixture.
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