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 Nm^(-2)`
C. `8 xx 10^4 Nm^(-2)`
D. 0.25 atm

Answer

C

Explanation

Given that, pressure of a 1 : 4 mixture of `H_2 and O_2` enclosed in a vessel is one atmosphere. This suggests that the moles ratio of `H_2 and O_2` is 1:4 Thus, partial pressure of dioxygen `(O_2)` is given as
`therefore `Partial pressure of `O_2 = ` mole fraction of `O_2 xx` total pressure of mixture ` = (4)/(1+4) xx 1 = 4/5 xx 1 atm`
`=0.8 atm = 0.8 xx 10^5 Nm^(-2) = 8 xx 10^4 Nm^(-2)`