Answer :
Answer:
Mole fraction of [tex]O_{2}[/tex] = 0.42
Moles fraction of Ar = 0.037
Explanation:
Let's assume all the four gases and their mixture behave ideally.
According to Dalton's law of partial pressure for mixture of ideal gases-
[tex]P_{i}=x_{i}P_{total}[/tex]
where [tex]P_{i}[/tex] and [tex]x_{i}[/tex] are partial pressure and mole fraction of "i"-th gas respectively. [tex]P_{total}[/tex] is total pressure of gaseous mixture.
Here [tex]P_{total}[/tex] = [tex]P_{N_{2}}+P_{O_{2}}+P_{Ar}+P_{He}[/tex]
= (3.5+2.8+0.25+0.15) atm
= 6.7 atm
So [tex]x_{O_{2}}=\frac{P_{O_{2}}}{P_{total}}[/tex] = [tex]\frac{2.8atm}{6.7atm}[/tex] = 0.42
[tex]x_{Ar}=\frac{P_{Ar}}{P_{total}}[/tex] = [tex]\frac{0.25atm}{6.7atm}[/tex] = 0.037