The partial pressures of CH 4, N 2, and O 2 in a sample of gas were found to be 183 mmHg, 443 mmHg, and 693 mmHg, respectively. What is the mole fraction of nitrogen?

Mole fraction N₂ = 0.336

Explanation:

Mole fraction of a gas can be determined in order to know the partial pressure of the gas, and the total pressure, in the mixture.

Total pressure in the mixture: Sum of partial pressure from all the gases

Total pressure = 183 mmHg + 443 mmHg + 693 mmHg = 1319 mmHg

Mole fraction N₂ = Partial pressure N₂ / Total pressure

443 mmHg / 1319 mmHg = 0.336

Remember that mole fraction does not carry units

The mol fraction of N2 is 0.336

Explanation:

Step 1: Data given

Partial pressure CH4 = 183 mm Hg

Partial pressure N2 = 443 mm Hg

Partial pressure O2 = 693 mm Hg

Step 2: Calculate total pressure

Total pressure = partial pressure CH4 + partial pressure N2 + partial pressure O2

Total pressure = 183 mm Hg + 443 mm Hg + 693 mm Hg

Total pressure = 1319 mm Hg

Step 3: Calculate mol fraction

Mol fraction = partial pressure / total pressure

Mol fraction N2 = 443 mm Hg / 1319 mm Hg

Mol fraction N2 = 0.336

The mol fraction of N2 is 0.336