Equal weights of ethane and hydrogen are mixed in an empty container at `25^(@)C`. The fraction of the total pressure exerted by hydrogen is

Options

A. `1 : 2`
B. `1 : 1`
C. `1 : 16`
D. `15 : 16`

Answer

D

Explanation

Mol. Mass of ethane `(C_(2)H_(6)) = 30`
Mol. Mass of `H_(2) = 2`
Let mass of each gas taken `= 60 g`
`n_(C_(2)H_(6)) = (60)/(2) = 2, x_(H_(2)) = (60)/(2) = 30`
`p_(H_(2)) = (30)/(30 + 2) = (30)/(32) = (15)/(16)`
`p_(H_(2)) = x_(H_(2)) P_("Total")`
`p_(H_(2))//P_("Total") = x_(H_(2)) = 15//16`