changing equilibrium position

[andy456]

I have a really dumb question that i need help with.... what i want to know is if  dilution can increase the equilibrium position?? thanks

[Martoman]

No it wouldn't.

[andy456]

Ok thanks so it only ever decreases the equilibrium position. I thought that was right but I was just double checking... Thankyou

[kenhung123]

Correct me if I am wrong but I thought alteration is only shift left or right?

[Mao]

Dilution can shift it left/right [equilibrium position], but it can't change the equilibrium constant K.

An example of shift to the right is dissociation of acetic acid, where dilution increases %ionisation.

[stonecold]

Will dilution always cause the concentration fraction to initially drop? Because that is what it says in A+ notes.

It has me rather confused...

[Martoman]

After actually learning this it makes sense.

If you dilute something then it will decrease pressure. This means that it will move to the side where there are more particles. Thus the position changes.

K doesn't change. Sure the concentration fraction will decrease but it will increase in such a way that it maintains K.

[stonecold]

yahh, I get what will happen, i just mean initially, like as soon as the change is made...

why does it decrease?

even if the number of particles on either side of the reaction is the same, A+ notes says it will decrease after dilution.

[Martoman]

yeah.... obviously.... think

Increase in denominator means a decrease in concentration..... thus intially the all decrease

[fady_22]

After actually learning this it makes sense.

If you dilute something then it will decrease pressure. This means that it will move to the side where there are more particles. Thus the position changes.

K doesn't change. Sure the concentration fraction will decrease but it will increase in such a way that it maintains K.

I wouldn't say pressure, but rather decrease in the overall concentration of particles. Therefore, there would be a net reaction reaction in the direction of most particles, to partially oppose the decrease in overall concentration.

[Martoman]

pressure proportional to concentration. Same idea, however more applicable to gases.

[Blakhitman]

Dilution can shift it left/right [equilibrium position], but it can't change the equilibrium constant K.

An example of shift to the right is dissociation of acetic acid, where dilution increases %ionisation.

Ethanoic acid...oldie

[fady_22]

pressure proportional to concentration. Same idea, however more applicable to gases.

Yep.

I don't think dilution would significantly change the pressure in the solution, though. Concentration is the better term to use in this situation.

[lisafaustina]

Dilution will cause the reaction to make a net shift to the side with more molecules

[physics]

equilibrium postion does not change. K constant is only changed due to temperature. the equilibrium may shift but not change.