We are asked to calculate the partial pressure of Nitrogen in the air at 1 atm.
Recall that Dalton's Law of Partial Pressure states that the total pressure of a mixture of gases can be defined as the sum of the pressures of each individual gas:
Therefore, the partial pressure of an individual gas is equal to the total pressure multiplied by the mole fraction of that gas, as in:
Pi = Partial Pressure of a gas = Partial Pressure of Nitrogen gas = unknown = x
PTotal= Total Pressure = 1 atm
Xi= mole fraction of a gas = mole fraction of Nitrogen
Air is about 78.0% nitrogen molecules and 21.0% oxygen molecules. Several other gases make up the remaining 1% of air molecules. What is the partial pressure of nitrogen in air at atmospheric pressure (1.0 atm)?