Question

At 400$K$, the root mean square speed of gas '$X$' (molar mass 40) is equal to most probable speed of '$Y$' at 60$K$.The molar mass of gas '$Y$' is .....

Answer 1

As we know,
$u_{rms}=\sqrt{3RT/M}$
$u_{mp}=\sqrt{2RT/M}$
According to given conditions,
$\sqrt{3R\ast 400/40}=\sqrt{2R\ast 60/M}$
$M=4$