Under identical conditions of temperature, the density of a gas `X` is three times that of gas `Y` while molecular mass of gas `Y` is twice that of `X`. The ratio of pressure of `X` and `Y` will be

Options

A. 6
B. `1//6`
C. `2//3`
D. `3//2`

Answer

A

Explanation

`rho=(PM)/(RT)implies P=(rhoRT)/(M)`
`P_(x)=(rhoxxRT)/(M_(x)) " " P_(y)=((rho_(x)RT)/(3))/(2Mx)`
`6P_(y)=(rho_(x)RT)/(M_(X))`
`:. 6P_(Y)=P_(X) " " (P_(X))/(P_(Y))=6`