Consider a sample of oxygen behaving like an ideal gas. At $300 \mathrm{K}$, the ratio of root-mean-square (RMS) velocity to the average velocity of the gas molecule would be :

(Molecular weight of oxygen is $32 \mathrm{g} {\mathrm{mol}}^{-1}; R=8.3 \mathrm{J}{ \mathrm{K}}^{-1}{ \mathrm{mol}}^{-1}$)

• A

  $\sqrt{\frac{3}{3}}$
• B

  $\sqrt{\frac{8}{3}}$
• Correct answer
  C

  $\sqrt{\frac{3\pi }{8}}$
• D

  $\sqrt{\frac{8\pi }{3}}$

Hence, the correct answer is option: 'C'.