At `27^@` C, a closed vessel contains a mixture of equal weights of helium (mol. wt. = 4 ), methane (mol. wt. =16) and sulphur dioxide (mol. wt = 64). The pressure exerted by the mixture is 210 mm. If the partial pressures of helium, methane and sulphur dioxide are `P_(1)`, `P_(2)` and `P_(3)` respectively, which one of the following is correct ?

Options

A. `P_3 gt P_2 gt P_1`
B. `P_1 gt P_2 gt P_3`
C. `P_1 gt P_3 gt P_2`
D. `P_2 gt P_3 gt P_1`

Explanation

`n_(He) = x/4 = 16y , n_(CH_4) = x/(16) = 4y , n_(SO_2) = (x)/(64) = y`
`X_(He) = 16/21, X_(CH_4) = 4/21 , X_(SO_2) = 1/21`
`P alpha x implies P_1 > P_2 > P_3` .