Answer:
Explanation:
The partial pressure of a gas in a mixture is equal to the mole fraction of the gas multipplied by the total pressure.
The mole fraction of a component in a mixture is equal to the number of moles of the component divided by the total number of moles in the mixture.
In the mixture given there are:
- 0.5 mol He,
- 0.09 mol CO₂,
- 0.75 mol O₂, and
- 1.5 mol At.
Hence, the gas with greatest number of moles, and, consequetly, greatest mole fraction and highest partial pressure is At.