Q27 / 90 · KVPY 2016 (SB/SX) · Chemistry
The ratio of root mean square velocity of hydrogen at $50 \mathrm{~K}$ to that of nitrogen at $500 \mathrm{~K}$ is closest to
- Correct answerA$1.18$
- B$0.85$
- C$0.59$
- D$1.40$
Solution
$\mathrm{V}_{\mathrm{rms}}=\sqrt{\frac{3 \mathrm{RT}}{\mathrm{M}}}$
$\frac{\left(\mathrm{V}_{\mathrm{rms}}\right)_{\mathrm{H}_{2}}}{\left(\mathrm{~V}_{\mathrm{rms}}\right)_{\mathrm{O}_{2}}}=\frac{\sqrt{\frac{3 \times \mathrm{R} \times 50}{2}}}{\sqrt{\frac{3 \times \mathrm{R} \times 500}{28}}}=1.18$
Hence, the correct answer is option: 'A'.