Question

A mixture of .250 moles O2, .297 moles N2, and .134 moles Ar has a total pressure of 1.95 atm. What is the mole fraction of O2 and what is the partial pressure of O2?

Answer 1

Mole fraction = `0.367`
Partial pressure = `"0.716 atm"`

Explanation:

`"Mole fraction of a gas"=("Number of moles of gas")/("Total moles of gas")`

For `O_2`:

`"Mole fraction of"` `O_2`

`= 0.250/(0.250+0.134+0.297)=0.250/0.681~~0.367`

`"Partial pressure of a gas" = "Mole fraction" xx "Total pressure"`

For `O_2`:

`"Partial pressure of"` `O_2`

`= 0.367 xx "1.95 atm" ~~ 0.716` `"atm"`