A sample of air in the rain forest contains 72.5% N2, 15.7% O2, 1.6% CO2, and 10.2% H2O (mole percent). Suppose exhaled air is at a pressure of 750.0 mm Hg. Calculate the partial pressures of nitrogen, oxygen, carbon dioxide, and water.
Answers
Given info : A sample of air in the rain forest contains 72.5% N2, 15.7% O2, 1.6% CO2, and 10.2% H2O (mole percent). Suppose exhaled air is at a pressure of 750.0 mm Hg.
To find : The partial pressure of nitrogen, oxygen, carbon dioxide and water are ...
solution : mole fraction = mole percent/100
so, mole fraction of N₂ = 72.5/100 = 0.725
mole fraction of O₂ = 15.7/100 = 0.157
mole fraction of CO₂ = 1.6/100 = 0.016
mole fraction of water = 10.2/100 = 0.102
a/c to Dalton's law of partial pressure,
partial pressure of a gas = mole fraction of the gas × total pressure
so partial pressure of N₂ = 0.725 × 750 = 543.75 mm Hg
partial pressure of O₂ = 0.157 × 750 = 117.750 mm Hg
partial pressure of CO₂ = 0.016 × 750 = 12 mm Hg
partial pressure of Water = 0.102 × 750 = 76.5 mm Hg