[xshadow]

I don't  understand its meaning....

A saturated solution is a solution with  also a precipitate??
Or only a solution without precipitate and with  Q = ks ??

For example if I know that I have a saturated solutuion of PbSO4 5*10^-4 M , can i say that
[Pb2+] is 5*10^-4 ??
(that is equal to say that in a saturated solution all the salt(s) ,here PbSO4 5*10-4M, is dissociated...


Thanks!!!!!!

[AWK]

Practically, we can expect that solution is saturated when for prolonged time some solid phase exists in an equilibrium with solution of this solid.

[xshadow]

Practically, we can expect that solution is saturated when for prolonged time some solid phase exists in an equilibrium with solution of this solid.

So if I know ONLY that I have a saturated solutuion of PbSO4 5*10-4M can I say that [Pb²⁺]=[SO4^2-]=5*10^-4 ??

Because I have this exercise:

Calculate the  potential "E"  of the cell:
Zn|ZnSO4 (5*10[sup-4[/sup]M  ||PbSO4 (saturated) (5*10^-4M |Pb

Now the nernst for E_Pb= E(PbSO4/Pb+SO42-) + 0,059/2 * log 1/[SO₄^2-]

But can I say that [SO₄^2-] = 5*10^-4 , because I have a saturated solution of PbSO4  5*10^-4M??

Thanks!!

[AWK]

But can I say that [SO42-] = 5*10-4 , because I have a saturated solution of PbSO4  5*10-4M??

It depends on stoichiometry of compounds. Let's take Ag₂SO₄. Saturated solution is 0.0144 M and concentration of sulfate is the same but concentration of Ag⁺ is 2 times greater.