Question

the mole percent of oxygen present in gaseous mixture containing 10 g of nitrogen and 8 g of o oxygen is?

Answer 1

no. of moles of N =10/14=0.714

no. of moles of O =8/16=0.5

mole % of Oxygen = 0.5/(0.714+0.5)×100

= 0.4117×100

= 41.17%

Answer 2

no.of moles=weight/gram molecular weight
then, oxygen mole =8/16=0.5mole
nitrogen mole=10/14=5/7=0.71mole
total mole percentage=1.21mole
then oxygen%=0.5/1.21×100=41.3% approximate