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hslove142331
Jan 20, 2010, 02:11 PM
Gas A is 16 times as dense as Gas B. how do their rates of diffusion compare? Which one diffuses faster? By how much?

I think B is diffuses faster.

I don't understand this problem.
how can I do compare both gas A and B

please help! Thank you

Also this is another problem.

Accordinto Graham's law, which gas will diffuse faster, CO or O2? How much faster?
root(32/28.01)=1.07
CO diffuse 1.07 times faster than O2 does.

I did This one, is it correct?

Thank you

Unknown008
Jan 21, 2010, 08:25 AM
The rate of diffusion of a gas is inversely proportional to it's relative mass.

The heavier a molecule, the slower it's rate of diffusion.

Yes, you're correct!

hslove142331
Jan 21, 2010, 11:38 AM
So, Gas B is more heavier and its more slower than Gas A.
Gas A diffuses faster. 16 times much faster?

Sorry, I am still confusing little bit. Thank you

Unknown008
Jan 22, 2010, 09:43 AM
You already got it right, it's B which is diffusing faster.

Density = Mass / Volume

The greater the mass, the greater the density.
Since the density of A is larger, A has a larger mass and is heavier.
Now, as mass increases (or density increases), the rate of diffusion decreases. (inverse relationship)

So, lighter molecules diffuse faster!
Heavier, slower.


Your other problem already showed it to you.
CO has a molecular mass of (12+16) = 28
O2 has a molecular mass of (16+16) = 32
So, CO (which is lighter) diffuses faster!

I hope it helped! :)

murigi.jon
Oct 26, 2011, 12:27 AM
equations for rate of diffusion