A reaction vessel contained 5 liters of a mixture of N2 and O2 gases at 25oC and 2 atm pressure. The oxygen in the mixture was completely removed by causing it to oxidize with an excess of electrically heated zinc wire contained in the vessel to non-volatile solid ZnO. The pressure of N2 that remained (measured again at 25oC) was 1.5 atm. What were the mole and mass percent of O2 in the starting mixture?
From the given data we can calculate the partial pressure of oxygen in the starting mixture:
p(O2) = p - p(N2) = 2 atm - 1.5 atm = 0.5 atm
where p = pressure of N2 and O2 mixture.
According to Dalton's law of partial pressures we ...