Some [tex]$N_2$[/tex] gas is mixed with some [tex]$O_2$[/tex] gas, and the sketch below shows a representative sample of the mixture. The total pressure of the mixture is measured and found to be 0.130 kPa.

\begin{tabular}{|c|c|c|c|}
\hline \multicolumn{4}{|c|}{Key} \\
\hline & Carbon & 0 & Hydrogen \\
\hline 0 & Nitrogen & 0 & Sulfur \\
\hline 0 & Oxygen & 0 & Chlorine \\
\hline
\end{tabular}

Calculate the mole fraction and partial pressure of each gas in this mixture. Round your answers to 3 significant digits. You may assume each gas behaves as an ideal gas.

\begin{tabular}{|c|c|c|}
\hline Gas & Mole Fraction & Partial Pressure \\
\hline [tex]$N_2$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] kPa \\
\hline [tex]$O_2$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] kPa \\
\hline
\end{tabular}



Answer :

Sure, let's solve this problem step-by-step.

Given:
- The total pressure of the gas mixture is 0.130 kPa.
- The mixture is composed of nitrogen ([tex]\(N_2\)[/tex]) and oxygen ([tex]\(O_2\)[/tex]) gas.
- We assume that the gases are present in equal amounts in the mixture.

### Step 1: Determine the mole fractions of [tex]\(N_2\)[/tex] and [tex]\(O_2\)[/tex]

Since it's given that nitrogen ([tex]\(N_2\)[/tex]) and oxygen ([tex]\(O_2\)[/tex]) gases are present in equal amounts, each gas will constitute half of the total number of moles. Hence, the mole fraction for each gas is:

[tex]\[ \text{Mole fraction of } N_2 = \frac{\text{Moles of } N_2}{\text{Total moles}} = 0.5 \][/tex]

[tex]\[ \text{Mole fraction of } O_2 = \frac{\text{Moles of } O_2}{\text{Total moles}} = 0.5 \][/tex]

### Step 2: Calculate the partial pressures of [tex]\(N_2\)[/tex] and [tex]\(O_2\)[/tex]

The partial pressure of a gas in a mixture can be calculated using its mole fraction multiplied by the total pressure of the mixture.

[tex]\[ \text{Partial pressure of } N_2 = \text{Total pressure} \times \text{Mole fraction of } N_2 \][/tex]

[tex]\[ \text{Partial pressure of } O_2 = \text{Total pressure} \times \text{Mole fraction of } O_2 \][/tex]

Given the total pressure is 0.130 kPa:

[tex]\[ \text{Partial pressure of } N_2 = 0.130 \, \text{kPa} \times 0.5 = 0.065 \, \text{kPa} \][/tex]

[tex]\[ \text{Partial pressure of } O_2 = 0.130 \, \text{kPa} \times 0.5 = 0.065 \, \text{kPa} \][/tex]

### Final Results:

[tex]\[ \begin{array}{|c|c|c|} \hline \text{Gas} & \text{Mole Fraction} & \text{Partial Pressure (kPa)} \\ \hline N_2 & 0.500 & 0.065 \\ \hline O_2 & 0.500 & 0.065 \\ \hline \end{array} \][/tex]

Here, we have calculated the mole fraction and partial pressure for each gas in the mixture:

- The mole fraction of [tex]\(N_2\)[/tex] is 0.500 and its partial pressure is 0.065 kPa.
- The mole fraction of [tex]\(O_2\)[/tex] is 0.500 and its partial pressure is 0.065 kPa.