If $r_1, r_2$ and $r_3$ represent the most probable speeds of three different gases at the same temperature…
If $r_1, r_2$ and $r_3$ represent the most probable speeds of three different gases at the same temperature as shown in figure with molar masses $M_1, M_2$ and $M_3$ respectively. The correct order of molar masses of these gases is
$M_1>M_3>M_2$
$M_3>M_2>M_1$
$M_2>M_1>M_3$
$M_2>M_3>M_1$
Solution
In the direction of $x$-axis $r_3$ increases and for same temperature most probable speed
$
\propto \frac{1}{\sqrt{\text { molar mass }(M)}}
$
Thus, $M_2>M_1>M_3$
