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Q.
A bulb contains one mole of hydrogen mixed with one mole of oxygen at temperature $T$. The ratio of $r.m.s.$ values of velocity of hydrogen molecules to that of oxygen molecules, is
Given: One mole of hydrogen mixed with one mole of oxygen.
We know that r.m.s. velocity
$\left(v_{rms}\right)=\sqrt{\frac{3RT}{M}}\mu \sqrt{\frac{1}{M}}$
or $\frac{\left(v_{rms}\right)_{H}}{\left(v_{rms}\right)_{O}}=\sqrt{\frac{M_{O}}{M_{H}}}=\sqrt{\frac{32}{2}}=\frac{4}{1}.$
or $\left(v_{rms}\right)_{H} : \left(v_{rms}\right)_{_O}= 4 : 1.$