Solubility of compound in solutions other than Water

[djdevine19]

So I'm studying solubility rules and such in chemistry and everything is fine and dandy except when the solution is something other than water. Here's 2 examples that my teacher gave us that I have no idea how to do:

BaCO3, BaSO3 and BaSO4 are all slightly soluble in water. The first 2 dissolve in HCl but BaSO4 doesn't. Why?

AgCl, Hg2Cl2 and PbCl2 are all slightly soluble in water. But AgCl dissolves in ammonia solution while the other 2 dont. Why?

I understand the fact that all of these are slightly soluble in water from the solubility rules. I'm just not clear about how to approach these problems involving a solvent other than water.

Any help is appreciated!
Thanks,
David

 

[symbolipoint]

You have not really discussed solvents other than water. Your HCl and your ammonia, seem assumed to be in aqueous solution (meaning in water).

Barium carbonate does not quite dissolve in HCl solution; it decomposes, liberating carbon dioxide and forming Barium Chloride. I'm not sure about the sulfite - maybe something similar, liberating sulfur dioxide?

Silver salts may dissolve in ammonium hydroxide solution because the Ag+ forms coordination complexes with ammonia, and the complex is solube. The mercury and the lead also form coordination complexes with ammonia.

 

[Kushal]

actually BaCO3 and BaSO3 react with the acid, to give CO2 and SO2 respectively. BaSO4 doesn't react. You may think of it like H2SO4 is a stronger acid than HCl, hence the HCl cannot displace the SO42-.

and i agree with symbolipoint about the complexes.