Respuesta :

Answer:

  • At.

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.