[NYM]

Is CaSO4 soluble in water? Wikipedia contradicts itself:

From http://en.wikipedia.org/wiki/Solubility#Solubility_of_ionic_compounds_in_water:
Soluble: sulfates (except Ag+, Pb2+, Ba2+, Sr2+ and Ca2+)

From http://en.wikipedia.org/wiki/Solubility_chart: Slightly soluble.

The same question with CuX2, where X is Cl-, Br- and I.

Thank you.

[Borek]

That's because there are no totally insoluble salts. They all dissolve to some extent. Saturated solution of NaCl is close to 6M, saturated solution of AgI is arounf 10^-9M if memory serves me well. CaSO₄ is generally considered insoluble, but of many insoluble salts it is one of the best soluble

[NYM]

Great, thanks!