Posted by Anon on Sunday, March 17, 2013 at 9:53pm.
The Ksp of PbBr2 is 6.60× 10^–6.
What is the molar solubility of PbBr2 in pure water?
What is the molar solubility of PbBr2 in 0.500 M KBr solution?
What is the molar solubility of PbBr2 in a 0.500 M Pb(NO3)2 solution?

Chemsitry  Devron, Sunday, March 17, 2013 at 10:40pm
PbBr2> Pb + 2Br
Ksp=[Pb][2Br]^2
6.60× 10^–6=[x][2x]^2
Solving for x
6.60× 10^–6=4x^3
6.60× 10^–6/4=x^3
(6.60× 10^–6/4)^1/3=x
B.)
PbBr2> Pb + 2Br
Ksp=[Pb][2Br]^2
6.60× 10^–6=[x][0.500M]^2
Solve for x,
6.60× 10^–6/[(0.500M)^2]=x
C.)
PbBr2> Pb + 2Br
Ksp=[Pb][2Br]^2
6.60× 10^–6=[0.500M][2x]^2
Solve for x,
6.60× 10^–6/[(0.500M)^2]=x
6.60× 10^–6/(0.500M)=4x^2
sqrt*{[6.60× 10^–6/(0.500M)]/4}=x 
To DevronChemsitry  DrBob222, Monday, March 18, 2013 at 1:30am
I don't disagree with any of the answers. Technically, and I realize this is nitpicking, I disagree with the set up. As an example,
PbBr2 ==> Pb^2+ + 2Br^
But Ksp says "the product of the molar solubility of the ions, each raised to the power indicated in the balanced equation, is a constant". I would write that as Ksp = (Pb^2+)(Br^)^2. It isn't twice the bromide ion x lead ion, it is THE bromide x lead ion. Yes, Pb ion is x and Br is 2x but 2x is THE bromide ion, not twice the bromide, but it is twice the PbBr2 that dissolves which is why it's 2x to begin with. 
Chemsitry==> Dr. Bob222  Devron, Monday, March 18, 2013 at 1:52am
I understand. That is why I worked on a problem and developed a headache when I couldn't figure out why the answer doubled compared to the answer that I calculated. If I set up the way that you mentioned then I would not have ran into that problem, and I can prevent others from performing the same mistake. Thank you for the advice. Also, I do not consider it nitpicking. I always thought it was nickpicking. We learn something new everyday.

Chemsitry Nits  Ken, Monday, March 18, 2013 at 3:52am
I lent my sleeping bag to a coworker once, when I used it the next night I woke up suddenly, feeling something crawling in my crotch. I spent the next 2 hours picking the critters off. then I went cross eyed picking nits. I got them all. Unpicked nits can grow into a HUGE problem. Never think you are being to thorough, especially in chemistry!!

Chemsitryljpo;ll[;kjjp['  jl7896+5565, Tuesday, November 25, 2014 at 3:18am
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