[DevaDevil]

indeed

[Rutherford]

indeed

Ok thank you. Now I only need solubility rules for compounds with F(-) anion.

[Arkcon]

indeed

Ok thank you. Now I only need solubility rules for compounds with F(-) anion.

Just about every binary metal fluoride salt is insoluble.  Some lists are better than others, but they sorta say that, like this one.

[Rutherford]

So, for example, NaF is insoluble?

[Arkcon]

So, for example, NaF is insoluble?

Nope, slightly soluble, and potassium fluoride even more so.  See, hoping for a perfect table to memorize is a fruitless search.  Generally, fluorine, the most electronegative element, holds it's ionic partner's electrons so strongly, that water can't solvate it.  Generally, ionic solids made of alkali metals are soluble, for reasons I don't know.   Which one wins in this case is hard to predict without advanced knowledge of atomic orbital theory, or memorization.

[Rutherford]

Ok, then nothing about fluorine, but I still don' understand the solubility for HCO3-,HSO4- and HPO4-. I checked the answers in my book from the problems I posted and there says that Ca(HCO3)2 is soluble and CaHPO4 ins't, why?

[vmelkon]

HCO3-, I'm getting the impression that it depends on the metal ion. You can have solid NaHCO3 and probably the other group 1 elements but I'm getting the impression that you can't with other elements.
From my searches, it seems HCO3- salts of group 2 elements (Mg and Ca) are more soluble than their CO3 versions. However, I think they exist in solution only.

I think that most HCO3 salts are unstable. For example, to test if road salt is CaCl2, add it to solution of NaHCO3. If it fizzes and you get a white solid, it is CaCO3. You'll probably have some minor amount of Ca2+ and HCO3- in solution.

http://www.newton.dep.anl.gov/askasci/chem07/chem07142.htm

[Arkcon]

Well, the teacher has made it harder, because the standard solubility rules tend to only cover carbonates and phosphates, and the H+ tends to muddy effects.  It seems that calcium bicarbonate only exits in dilute solution, and that is an outlier, most others are insoluble or don't exist at all.  The only conclusion I can come to is the teacher expects you to memorize all this, unless it was mentioned how H+ stabilizes the ions in solution.

[Rutherford]

I asked this because we did't mention a thing.