Relate a component’s partial pressure to its mole fraction.
Difficulty
Beginner
Read time
3 min
Prerequisites
Basic algebra and molar quantities
Source
OpenStax, Chemistry 2e, §9.3Adapted from Teng-Jui Lin’s CHEM 145 equation sheet. The linked textbook reference was used to check the equation and its physical context. Pending editorial review.
Adapted from Teng-Jui Lin, Equation Sheets, under CC BY 4.0.
FormuLab adapted notation and chemical symbols, added variable meanings, units, applicability conditions, and an original worked example.
In an ideal gas mixture, each component contributes pressure in proportion to its mole fraction. The partial pressures add to the mixture’s total absolute pressure.
| Symbol | Meaning | Units |
|---|---|---|
| Partial pressure of component i | ||
| Mole fraction of component i | ||
| Total absolute mixture pressure |
Estimate the pressure contribution of one gas.
Separate a gas’s partial pressure from the total pressure of a mixture.
An ideal gas mixture has total absolute pressure 200 kPa and oxygen mole fraction 0.210. Find the oxygen partial pressure.
Adapted from Teng-Jui Lin’s CHEM 145 equation sheet. The linked textbook reference was used to check the equation and its physical context. Pending editorial review.
Adapted from Teng-Jui Lin, Equation Sheets, under CC BY 4.0.
FormuLab adapted notation and chemical symbols, added variable meanings, units, applicability conditions, and an original worked example.
Assumptions
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