The density of gas `A` is twice that of B at the same temperature the molecular weight of gas B is twice that of A. The ratio of pressure of gas A and B will be :

Options

A. `1:6`
B. `1:1`
C. `4:1`
D. `1:4`

Answer

3

Explanation

`d_(A)=2d_(B)," "3M_(A)=M_(B)," "PM=dRT`
`(P_(A))/(P_(B))xx(M_(A))/(M_(B))=(d_(A))/(d_(B))xx(RT)/(RT)`
`(P_(A))/(P_(B))xx(1)/(2)=2`
`(P_(A))/(P_(B))=(4)/(1)`