Since there's already Pb ions in the solution it's less soluble so you get Ksp= [Pb]^2. Feel free to pm me if you wanna ask about gchem/math. My test is tomorrow but helping others out and talking might calm me down a bit

Since there's already Pb ions in the solution it's less soluble so you get Ksp= [Pb]^2. Feel free to pm me if you wanna ask about gchem/math. My test is tomorrow but helping others out and talking might calm me down a bit

On second thought, I still don't exactly understand it. I ran it by a few other kids from my review class, and they seem to be stumped as well. @LuckBloodandSweat, do you think you'd mind elaborating further? (i'm doing my best to help ease your nerves here!)

ha yes, I was able to see it. No worries, and thank for the awesome response! But I unfortunately am still unclear as to why it is X instead of 2X exactly. I understand that there's a common ion effect taking place here, but how exactly did you calculate/determine that it is X instead of 2X for I- ions? Did you divide by two?

I think the way any common ion effect works is that you just take away the coefficient you'd normally have but you would still square/cube/whatever function it would normally have. Sorry if I didn't make that clear.

I think the way any common ion effect works is that you just take away the coefficient you'd normally have but you would still square/cube/whatever function it would normally have. Sorry if I didn't make that clear.

Hmm ok. Yeah, that does seem to be the case, I'm just still a bit curious for even more elaboration as to exactly what is going on here and how the common ion effect affects the coefficients.

Thank you very much for the help!

I wonder, @orgoman22, would you possibly be able to elaborate on this further?

Maybe it has something to do with when you throw I ions in the solution it's not like you add them in a +2X fashion. But when I combined with Pb it's gonna be 2I's for every 1 Pb. I think it's pretty common (haha) for common ion effect problems. Basically you don't have the coefficients when you do the ice table because the ions aren't dissociating in a set fashion. You're just throwing ions in the solution which then they combine in an orderly fashion (for example 2 I's for every Pb) to form the precipitate. maybe someone else can add something. Orgoman22 would definitely be your best bet haha

Recall Ksp is the Products divided by the Reactants.......like any equilibrium constant, the solid is not used. PbCl2 dissociates into Pb+2 ions and two Chloride ions.......thus the Ksp is the product of The Pb+2 and Cl- squared. I square the Cl- since two chloride ions are dissociated .This is a very very important problem. Please redo the problem. If you need more work on this, I like the Raymond Chang text book as well as Brown and LeMay.