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Question
Consider a sample of oxygen at 300 K. Find the average time taken by a molecule to travel a distance equal to the diameter of the earth.
Use R=8.314 JK-1 mol-1
Solution
Here,
\[ V_{avg} = \frac{\sqrt{8RT}}{\sqrt{\pi M}} = \frac{\sqrt{8 \times 8 . 314 \times 300}}{\sqrt{3 . 14 \times 0 . 032}}\]
\[ = 441 . 44 \text { m/s }\]
We know
\[T = \frac{\text { Distance }}{\text { Speed }} = \frac{6400000 \times 2}{441 . 44}\]
\[ = \frac{28996.01 h}{3600}=8.054h=8h\]
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