• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

Equiliberium and Concentration question (2 Viewers)

carlytse621

Member
Joined
Feb 7, 2008
Messages
209
Location
Behind you ;)
Gender
Female
HSC
2009
i put:

1st change = temp increase
2nd change = CO concentration decreased manually.
3rd change = pressure reduced
I put the same thing :)
but the last one i put total pressure is decreased so all concentration drop dramatically
same thing anyway....xD
 
Last edited:

carlytse621

Member
Joined
Feb 7, 2008
Messages
209
Location
Behind you ;)
Gender
Female
HSC
2009
Pressure can't change the total concntration... but it can shift it
hmmmm.....
i said Pressure is proportional to the inverse of volume
and since concentration is proportional to the inverse of volume as well
therefore Pressure is portional to concentration.... : S
maths trick~
 

Gibbatron

Member
Joined
Mar 20, 2009
Messages
339
Gender
Male
HSC
N/A
Pressure can't change the total concntration... but it can shift it
Pressure wont change the total amount of each substance present but it will change how much of each substance is present per unit volume, or concentration for short.
 

David.Lai

New Member
Joined
May 9, 2008
Messages
10
Gender
Male
HSC
2009
hmmmm.....
i said Pressure is proportional to the inverse of volume
and since concentration is proportional to the inverse of volume as well
therefore Pressure is portional to concentration.... : S
maths trick~
you are correct, that is what i put. The mathematical expression is actually described as Boyle's Law. In this question also, Le Chatliers principle must be stated and emphasised, as it is the cause of each effect. If the principle were to be false, these changes would not have occured, thus Le Chatliers principle is critical within each change.
 

walk

Midgely
Joined
Oct 10, 2004
Messages
16
Location
newcastle
Gender
Undisclosed
HSC
N/A
Cl2 went from 0.12 to 0.08 = drop of one third
CO went from .06 to .04 = a drop of one third
COCl2 went from .03 to .02 = a drop of one third


This is because the volume of the container was reduced by one third
 

Aerath

Retired
Joined
May 10, 2007
Messages
10,169
Gender
Undisclosed
HSC
N/A
Ohhh, shit. Did we have to say anything about volume beingreduced by a third? Lame. :p
 

Gibbatron

Member
Joined
Mar 20, 2009
Messages
339
Gender
Male
HSC
N/A
Ohhh, shit. Did we have to say anything about volume beingreduced by a third? Lame. :p
I hope not. I just said pressure on total system was reduced, shifting equilibrium to the right.
 

Aerath

Retired
Joined
May 10, 2007
Messages
10,169
Gender
Undisclosed
HSC
N/A
I hope not. I just said pressure on total system was reduced, shifting equilibrium to the right.
Yeah, that's what I said. Didn't pay that much attention to how much it dropped. :p
 

chuboy

Member
Joined
May 14, 2009
Messages
121
Location
Northern NSW
Gender
Male
HSC
2009
Cl2 went from 0.12 to 0.08 = drop of one third
CO went from .06 to .04 = a drop of one third
COCl2 went from .03 to .02 = a drop of one third


This is because the volume of the container was reduced by one third
Actually, the volume increased, thats why the concentration went down.

Although I just said they scooped 1/3 of the gases out (since they would have been evenly mixed) since I didn't think it was possible to change the shape of a container in such a way, and because there was less gas, the concentration decreased and the pressure decreased, pushing the equilibrium to the right.
 

walk

Midgely
Joined
Oct 10, 2004
Messages
16
Location
newcastle
Gender
Undisclosed
HSC
N/A
Yes....should have written that the volume increased by a third to make the concentrations drop like this ...thankx :D
 

Shoom

Member
Joined
Aug 26, 2008
Messages
694
Gender
Undisclosed
HSC
N/A
ok stupid me wrote this


first 4 minutes or wateva the systems at equilibrium, then theres a change, I said the temp is increased favouring the forward reaction, because its endothermic and I also said pressure was decreased, so to counteract the change the side with more moles of gas is favoured.


THEN STUPID ME, when they all dropped in the straight line I said the system was trying to restablish equilibrium, then it changed again and I once again said increase in temp and decrease in pressure, but not as much as before shown by the less steep curve of the graph.


:(:(
1/6 fuck.
 

matt527

New Member
Joined
Jul 7, 2009
Messages
2
Gender
Male
HSC
2009
you are correct, that is what i put. The mathematical expression is actually described as Boyle's Law. In this question also, Le Chatliers principle must be stated and emphasised, as it is the cause of each effect. If the principle were to be false, these changes would not have occured, thus Le Chatliers principle is critical within each change.
i think the 3rd one may be debatable for now ..

however ... i agreed with this guy...
Le'Chataliers principle most probably had to have been stated and refered to when describing each change if u wanted full marks
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top