[supehr]

So in this textbook i encountered this question for gas effusion through an orifice.
I solved it by placing:

?mol O₂ in the denominator and 2.2x10^-4 in the numerator like it's done in the example because O2 is a heavier gas and will effuse slower and N2 should effuse faster.
But the solution (attached) did it differently. I got 2.5x10^-4 and the solutions got 2.1x10^-4.

Why did they place oxygen in the numerator, even though it should diffuse slower? Can someone explain it to me. Thank you!

[supehr]

Oh i am talking about practice example A!

[Borek]

Sanity check: molar mass of oxygen is higher, so it should effuse slower, yet your result suggest more oxygen effused. Something is apparently wrong.

Graham's law is

[tex]\frac {Rate~of~effusion~of~gas_1}{Rate~of~effusion~of~gas_2} = \sqrt{\frac {M_2}{M_1}}[/tex]

It shouldn't matter which gas is which, as long as you are consistent.

[supehr]

Oh i see, thus oxygen takes more time and it should be less than one. That makes sense! I needed to re-read the notes didn't quite get it through my head  . Thank you