[Ski Dude]

Need to precipitate lead from a concentrated calcium chloride solution w/o precipitating out the calcium.  Hydroxide addition (to form lead hydroxide) causes CaO to form and precipitate.  NaSH addition (to form a lead sulfide) is useful, but has some odor problems, and the possibility of forming H2S.

Any other suggestions?

[Borek]

CrO₄^2-

[arnyk]

Check your solubility rules.  

Wait, so you're saying you have a concentrated CaCl2 solution WITH lead ions in it??  That sounds kind of wacky to me.

Ok let's say then it's a solution with Ca2+, Cl-, and Pb2+.

Add NaI to the solution, CaI2 is soluble and PbI2 will precipitate bright yellow.

Edit**:  But if those three initial ions were already in solution then the Pb2+ would have already reacted with the Cl- to form a precipitate.  

Hm, I guess I don't really understand the question then?  

[Borek]

Edit**:  But if those three initial ions were already in solution then the Pb2+ would have already reacted with the Cl- to form a precipitate.  

Hm, I guess I don't really understand the question then?  

Seems so

Have you ever heard about solubility product?

[arnyk]

I do now.  

For the Ksp values do you have to just remember them like molar masses or is there another way?

[Borek]

For the Ksp values do you have to just remember them like molar masses or is there another way?

It doesn't make sense to remember them. On the qualitative level you have solubility rules (and these are worth of remembering), on the quantitative level you can always check in tables.