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

Question

Philoid · Accepted Answer

Let the weight of dihydrogen be 20 g and the weight of dioxygen be 80 g.

Then, the number of moles of dihydrogen:

n(H₂) = 20/2 = 10 moles

The number of moles of dioxygen:

n(O₂) = 80/32 = 2.5 moles

Given that,

Total pressure of the mixture, p(total) = 1 bar

Then, partial pressure of dihydrogen:

= 0.8 bar

Hence, the partial pressure of dihydrogen is 0.8 bar.