Air is made of nitrogen, carbon dioxide, and small amounts of other gases. What is the pressure of O2 at 1 atm if PN2 = 593.4 mm Hg, PCO2 = 3.0 mm Hg, and Pothers = 7.1 mm Hg?

Answer 1

According to Dalton's law of partial pressure, the total pressure (P_T) equals the sum of the individual partial pressure of each gas. Since we are dealing with air, we will assume the total pressure equals 760.0 mm Hg.

P_T = P_N2 + P_O2 + P_CO2 + P_others

760.0 = 593.4 + P_O2 + 3.0 + 7.1

P_O2 = 760.0 - 593.4 - 3.0 - 7.1 = 156.5 mm Hg