the pressure of a `1 : 4` mixture of dihydrogen and dioxygen enclosed in a vessel is one atmosphere. What would be the partial pressure of dioxygen ?

Options

A. `0.8 xx 10^(5)` atm
B. `0.008 N m^(-2)`
C. ` 8 xx 10^(4) N m^(-2)`
D. 0.25 atm

Answer

C

Explanation

`p_(O_(2))=x_(O_(2))xx P_("total")`
Given : `P_("total")=1 atm, x_(O_(2))=(4)/(5)`
`p_(O_(2))=(4)/(5)xx1 = 0.8 atm`
`(because 1 atm = 1.01325xx10^(5)"Pa or N m"^(-2))`
`=0.8xx10^(5)N m^(-2)=8xx10^(4)N m^(-2)`