Question

A mixture of 2 moles of helium gas (`(atomic mass)=4a.m.u`) and 1 mole of argon gas (`(atomic mass)=40a.m.u`) is kept at 300K in a container. The ratio of the rms speeds `((v_(rms)(helium))/((v_(rms)(argon))` is
A. `0.32`
B. `0.45`
C. `2.24`
D. `3.16`

Answer 1

Correct Answer - D
`(V_(RmS_(He)))/(V_(RmS_(Ar)))=sqrt((3RT)/(m_(He)))/sqrt((3RT)/(m_(Ar)))`
`= sqrt((m_(Ar))/(m_(He))) = sqrt((40)/(4)) = sqrt(10)~~3.16`