A mixture of dihydrogen and dioxygen at one bar pressure contains 20% by weight of dihydrogen. Calculate the partial pressure of dihydrogen.

Options

A. 0.8 bar
B. 0.4 bar
C. 1.6 bar
D. 3.2 bar

Answer

A

Explanation

Let the weight of mixture = 100 g
Given weight
Mole = `("Given weight")/("Molecular weight")`
Weight of dihydrogen = 20 g
Moles of dihydrogen = 10
Weight of dioxygen = 80 g
Moles of dioxygen = 5
`P_(H_(2)) = P_("Total").X_(H_(2))`
`= P_("Total") xx n_(H_(2))/(n_(H_(2)) xx n_(O_(2)))`
`= 1 xx (20//2)/(20/2 + 80/32)` bar = 0.8 bar (approx)