A gaseous mixture of O_{2} and N_{2} contains 40.8% nitrogen by mass. What is the partial pressure of oxygen in the mixture if the total pressure is 605 mmHg?

Express you answer numerically in millimeters of mercury.

Dalton's law states that the total pressure, *P*_{total}, of a mixture of gases in a container equals the sum of the pressures of each individual gas:

${\mathbf{P}}_{\mathbf{total}}\mathbf{=}{\mathbf{P}}_{\mathbf{1}}\mathbf{+}{\mathbf{P}}_{\mathbf{2}}\mathbf{+}{\mathbf{P}}_{\mathbf{3}}\mathbf{+}\mathbf{.}\mathbf{.}\mathbf{.}$

The *partial pressure* of the first component, *P*_{1}, is equal to the mole fraction of this component, *X*_{1}, times the total pressure of the mixture:

${\mathbf{P}}_{\mathbf{1}}\mathbf{=}{\mathbf{X}}_{\mathbf{1}}\mathbf{\times}{\mathbf{P}}_{\mathbf{total}}$

The *mole fraction*, *X*, represents the concentration of the component in the gas mixture, so

${\mathbf{X}}_{\mathbf{1}}\mathbf{=}\frac{\mathbf{moles}\mathbf{}\mathbf{of}\mathbf{}\mathbf{component}\mathbf{}\mathbf{1}}{\mathbf{total}\mathbf{}\mathbf{moles}\mathbf{}\mathbf{in}\mathbf{}\mathbf{mixture}}$

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