Equal masses 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=1g`
`"Mole fraction of oxygen"=(w//32)/(w//32+w//16)=(1)/(3)`
Let the total pressure =p
Pressure exerted by oxygen (partial pressure)
`=x_(O_(2))xxP_("total")=Pxx(1)/(3)`