Question

At 400K, the root mean square (rms) speed of a gas X ( molecular weight `=40 )` is eqal to the most probable a speed of gas Y at 60K. The molecular weight of the gas Y is

Answer 1

Correct Answer - 4
`u_(rms)=alpha_(mp)`
`sqrt((3RT)/(M_(X)))= sqrt((2RT)/(M_(Y)))`
`= sqrt((3R xx 400)/(40))=sqrt((2R xx 60)/(M^(Y)))`
`M_(Y)=4`