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Question
Give reason for the following:
Though hydrogen is lighter than air it cannot be collected by downward displacement of air.
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Solution
Since hydrogen is lighter than air. it is possible to collect the gas by downward displacement of air. But it is not safe to do so since a mixture of hydrogen and air can lead to an explosion.
RELATED QUESTIONS
For laboratory preparation of hydrogen, give the following:
chemical equation
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sodium
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\[\ce{Ca(OH)2 + H2}\]
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\[\ce{Al2(SO4)3 + H2}\]
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