Answer to Question #71401 in General Chemistry for Amos Chayee

Question

In a study of O2 uptake by muscle at high altitude, a physiologist prepares an atmosphere consisisting of 79 mole % N2,17 mole % 16O2 and 4.0 mole % 18O2 ( the isotope 18O2 will be measured to determine O2 uptake ...) The total pressure is 0.75atm to simulate high altitude. Calculate the mole fraction and partial pressure of 18O2 in the mixture

Answer 1

According to the data given, the mole fraction of 18O2 is 4.0%. Partial pressure P_i of the component can be calculated as:

P_i=x_i·P;
where x_i is the molar fraction of the gas in q mixture, P is the total pressure.

P_(O_2 18)=0.04·0.75 atm=0.03 atm.
Answer: Partial pressure of 18O2 in the mixture is 0.03 atm.