Solubility Rules for Gen Chem-Know???

[dsherida]

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Do you think we need to know specific rules like the solubility rules where you have to memorize like the solubility of a bunch of different atoms?

 

[Wilford Brimley]

Originally posted by dsherida
Do you think we need to know specific rules like the solubility rules where you have to memorize like the solubility of a bunch of different atoms?

It only takes a second to memorize. It couldn't hurt...

 

[zinjanthropus]

You should know salt solubility rules - basically that group I and group IIs are soluble, as well as ammonium. You should also know that Hg, Pb, and Ag aren't soluble unless they are perchlorates, nitrates, or acetates. Oh, and you should also know the general phase solubility rules - like solids tend to increase their solubility as temp increases, that gases tend to decrease their solubility as temp increases, and that gases tend to increase their solubility as pressure increases.

Along with that, you should understand Ksp and whether more salt will dissolve in a solution and what type of solution will form when a salt dissolves (acidic, basic, or neutral). Basically, if the cation is a group I or group II cation it's not going to react with water and an anion that's the conjugate base of a weak acid will react with water. If the cation reacts with water, the solution is acidic. If the anion reacts with water, the solution is basic. If they both can react look at the Ka/Kb values, and if neither the cation or anion can react it's neutral.

 

[greggth]

It seems to me that the most important thing for solubility is to have a solid understanding of Ksp, ion product, and solubility and the calculations that interrelate these 3 things. (Also there was one practice question on the relationship between Ka and Ksp).