A mixture of oxygen and hydrogen gases at 1.5 bar pressure contains 30% by weight of hydrogen. Calculate the partial pressure(bar) of hydrogen gas.

wt. of H2=30g; mol. wt. of H2=2gmol−∴ no. of mol of H2= wt. / mol. wt. =30/2=15mol. wt. of O2=100−30=70g; mol. wt. of O2=2×16=32gmol−∴ no. of mol of O2= wt. / mol. wt. =70/32=2.1875molTotal no. of mol =15+2.1875=17.1875mol∴ Partial pressure of H2=nH2 Total no. of mol×Total pressure=1517.1875×1.5=1.31bar