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Question
Consider a mixture of oxygen and hydrogen kept at room temperature. As compared to a hydrogen molecule an oxygen molecule hits the wall
Options
with greater average speed
with smaller average speed
with greater average kinetic energy
with smaller average kinetic energy
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Solution
with smaller average speed
The average speed of molecules is given by \[\sqrt{\frac{8kT}{\pi m}}\] .
We observe that greater the mass, lesser is the average speed of the molecule. Since an oxygen molecule is heavier than a hydrogen molecule, the oxygen molecule will hit the wall with smaller average speed.
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