Equal mass of methane and oxygen are mixed in an empty container at `25^(@)`C. The fraction of the total pressure exerted by oxygen is:

Options

A. `2/3`
B. `1/3 xx 273/298`
C. `1/3`
D. `1/2`.

Answer

C

Explanation

Suppose the equal mass of methane and oxygen =w=1 g
Mole fraction of oxygen (X)=`(W//32)/(W//32+W//16)`
`(1/32)/(3/32)=1/3`
Let the total pressure `(P_(total))` be equal to P.
`:.` Pressure exerted by Oxygen (partial pressure)
`=XO_2 xxP_(total)=Pxx1/3`.