Question

Find the ratio of the root mean square speed of oxygen gas molecules to that of hydrogen gas molecules, if the temperature of both gases is the same.

• A. $\frac{1}{4}$
• B. $\frac{1}{16}$
• C. $\frac{1}{32}$
• D. $\frac{1}{8}$

Answer 1

Answer: (A)

$\frac{1}{4}$

Answer 2

$V_{rms} = \sqrt{(\frac{3RT}{M})}$
$V_{rms}\propto \frac{1}{\sqrt{m}}$
$\frac{(V_{rms})_{O_2}}{(V_{rms})_{H_2}} = \sqrt\frac{2}{32}= \frac{1}{4}$

So, the correct option is (A): $\frac 14$