Two vessels separately contain two ideal gases A and B at the same temperature, the pressure of A being twice that of B. Under such conditions, the density of A is found to be 1.5 times the density of B. The ratio of molecular weight of A and B is

Options

A. `3/4`
B. 2
C. `1/2`
D. `2/3`

Answer

A

Explanation

`rho/P = M//RT`
`rho_A = (P_AM_A)/(RT_A) , rho_B = (P_B M_B)/(RT_B)`
As` T_A = T_B , rho_A = 1.5 rho_B , P_A = 2P_B`
`:.rho_A/rho_B = P_A/P_B xx M_A/M_B`
`1.5 = 2 xx M_A/M_B rArr M_A/M_B = 3/4`