Root mean square velocity of gas molecules is `300 m//sec`. The `r.m.s` velocity of molecules of gas with twice the molecular weight and half the absolute temperature is :

Options

A. `300ms^(-1)`
B. `600ms^(-1)`
C. `75ms^(-1)`
D. `150ms^(-1)`

Answer

D

Explanation

rms velocity `C=sqrt((3pV)/(M))=sqrt((3RT)/(M))`
and the new rms velocity , `c_(1)=sqrt((3R(T//2))/((2M)))=(1)/(2)sqrt((3RT)/(M))`
`=(c)/(2)=(300)/(2)=150ms^(-1)`