Understanding Mole Fraction
The mole fraction of a component in a mixture is the ratio of the number of moles of that component to the total number of moles in the mixture.
Calculations
1. Total Moles: Add the moles of each gas: 0.25 mol O₂ + 0.75 mol N₂ + 1.50 mol CO₂ = 2.50 mol total
2. Mole Fraction of Oxygen (O₂):
* Mole fraction of O₂ = (Moles of O₂) / (Total moles)
* Mole fraction of O₂ = 0.25 mol / 2.50 mol = 0.10
3. Mole Fraction of Nitrogen (N₂):
* Mole fraction of N₂ = (Moles of N₂) / (Total moles)
* Mole fraction of N₂ = 0.75 mol / 2.50 mol = 0.30
4. Mole Fraction of Carbon Dioxide (CO₂):
* Mole fraction of CO₂ = (Moles of CO₂) / (Total moles)
* Mole fraction of CO₂ = 1.50 mol / 2.50 mol = 0.60
Summary
* Mole fraction of O₂ = 0.10
* Mole fraction of N₂ = 0.30
* Mole fraction of CO₂ = 0.60
Important Note: STP (Standard Temperature and Pressure) is not relevant for calculating mole fractions. Mole fractions are independent of temperature and pressure.
