[bravoghost]

Here's a question that's been bugging me:

Pb(OH)2 is slightly soluble in water. How would the amount of Pb(OH)2 that normally dissolves in 1 L of water be affected if the pH were 9.0?

I think that there would be less dissociation since the OH groups would be discouraged from leaving the Pb and making the solution more basic. Am I right? If it were a pH of 4, the opposite would be true - the OH would be "happy" to leave and combine with the H+ floating around.

[Borek]

On the very basic level you are right. Look into common ion effect.