NEET Solved Paper 2016 Question 23

Question: Equal moles of hydrogen and oxygen gases are placed in a container with a pin-hole through which both can escape. What fraction of the oxygen escapes in the time required for one-half of the hydrogen to escape?

Options:

A) 1/8

B) ¼

C) 3/8

D) ½

Show Answer

Answer:

Correct Answer: A

Solution:

  • $ {n _{H _2}}={n _{O _2}} $ and $ {t _{H _2}}={t _{O _2}} $ According to Graham’s law $ \frac{{r _{H _2}}}{{r _{O _2}}}=\sqrt{\frac{{M _{O _2}}}{{M _{H _2}}}}\Rightarrow \frac{v _1/t _1}{v _2/t _2}=\sqrt{\frac{32}{2}} $ $ \frac{1/2}{1/x}=\sqrt{16}=4 $ $ \frac{x}{2}=4 $
    $ \therefore $ $ x=8 $
    $ \therefore $ Fraction of $ O _2=1/8 $