Partial Pressures of gases Basic Composition of Air 79% Nitrogen o Oxygen 0% Carbon Dioxide In a mixture of gases, each gas exerts a partial pressure proportional to its mole fraction Total Pressure =sum of the partial pressures of each gas Total Pressure(at sea level) barometric 760 mm hs 760mm Hs Pgas=Pb X Fgas PN2=760X0.79=600.4mmHg PO2=760X0.21=1596mmHg5 Partial Pressures of Gases Basic Composition of Air • 79% Nitrogen • 21% Oxygen • ~ 0% Carbon Dioxide In a mixture of gases, each gas exerts a partial pressure proportional to its mole fraction. Total Pressure = sum of the partial pressures of each gas Pgas = Pb x Fgas PN2 = 760 x 0.79 = 600.4 mm Hg P02 = 760 x 0.21 = 159.6 mm Hg Total Pressure (at sea level) Pbarometric = 760 mm Hg Pb 760 mm Hg Pb