Question

The temperature at which $rms$ speed of $O_2$ is equal to that of neon at 300 $K$ is:

• A. 280 $K$
• B. 480 $K$
• C. 680 $K$
• D. 180 $K$

Answer 1

The correct option is B 480 $K$

As we know,

$U_{rms}=\sqrt{\frac{T}{M_w}}$

$T\propto M_w$
$\frac{T_{Ne}}{T_{{)}_2}}=\frac{20}{32}$
$T_{O_2}=480K$

Hence, the correct option is $\text{B}$