Question

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

Answer 1

Weight of H2 = 20 g in 100 g mixture

Weight of O2 = 80 g

***** of H2 = 20/2 = 10

***** of O2 = 80/32 = 5/2

Total ***** = 10 + 5/2 = 25/2

P'H2 = PT x mole fraction of H2 = 1 x 10/(25/2)

= 0.8 bar