- #36
Borek
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How are their pressures related?
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epenguin said:First check results for consistency.
You say pO2/pSO2= 0.5 but it isn't in your conclusions. - only a decimal point mistake or other?
Then I would like to say that - I don't know that this is always followed, but In my book equilibrium constants have to have units.
Well for reactions like A ⇔ B, or A + B ⇔ C + D the eq, constant is dimensionless, but in your case it has the dimensions of pressure and units of atm. Somebody else might use torr etc. but it could also have been concentrations and M (as I was assuming in my sketch). You could have done the whole thing in terms of concnetrations but I think it is equivalent reasoning and only units and their numbers different - hope this will be clear to you.
If and when this is right, I have not checked everything, you have done the first two steps of #14.
The next will be step 3. I think the equation is not as horrible as I first thought, but you can begin formulating that.
Moose100 said:Ptotal=pO2+pSO3+pSO2
pSO2/pSO3=0.152
pO2/pSO2= 0.5
Ptotal= 0.5pSO2 +pSO2/0.152 + pSO2
Ptotal=8.08pSO2
pSO2=2.73/8.08=0.338
pSO3=0.338/0.152=2.22
pO2= 0.169
k=[pSO2]2[pO2]/[pSO3]2
k=[0.338]2[0.169]/[2.22]2
k=3.9 × 10-3
Moose100 said:For
aA ↔ cC +dD
Ive got some kind of glitch here..geez.
K=[A]a/[C]c[D]d
If there is an unknown for say A and we know the rest we substitute X(or leave it as A) and solve. Knowing the rest of the values.
Moose100 said:
Also in you most recent post. The second problem was specifically saying the conc. of one of the reactants doubled so ONLY the initial doubles and not the whole term of 2.22-2x? I wrote 4.44-2x and got a correct answer. But want learn the distinction between that and the original problem of double the PRESSURE at equilibrium.(4.44-4x for this term and the others)
I think my issues come when they manipulate certain aspects of the equilibrium reaction as distinguished and described above. I feel like there is something that I need to nail down. Sometimes trial and error does that lol.
Moose100 said:Well we solved the first problem when the piston was moved in halfway doubling the pressure. THEN I added another question about the same system where they added the same amount of SO3 that was there and left the piston alone. The question then asks what is the conc at equilibrium. I mean I got the answer but I don't know if it's just a fluke.
Yes the answer is given. I am using schaums college chem.