any suggestion for memorizing solubility chart?

[dl9006]

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is there any tricks/tips to memorzing the solubility of compounds?
thanks!

 

[drpsuedonym]

I don't think you need it. If anyone knows I'm wrong, feel free to correct me, although I am pretty sure.

 

[Maygyver]

I thought we had to know it.

 

[heatwheat]

I took my test today, and I would suggest def. learning about solubility. I don't have any tricks however. Sorry...

 

[polarmolar]

There is a mnemonic that "contach" improved upon, do a search.

 

[harrygt]

YOu need to know the theory about solubility, understand it well, and be able to solve different types of problems [such as Ksp problems, etc]; however, there is no need to memorize the whole chart. Just know the very obvious ones [For example silver halides are usually insoluble. Salts with alkaline metals like KBr, NaCl, etc are always soluble. Whatever has NO3- in it is always soluble, and there are a couple more to this]. Don't memorize the whole chart, cause you will be wasting time and brain. GL

 

[klutzy1987]

Exactly, know group 1 is soluble also and know the general rules for solubility, and know what particular items are not soluble.

 

[jbravo12]

I usually have cool tricks to memorize, but for this one.. I could not come up with it. I suggest just looking at it over and over again and doing random self "pop-quizzes" by writing them all out on scratch paper.

The Kaplan BB lists 7 of them, and I just remember that the first 4 are the soluble ones, and the last 3 are the insoluble ones.

 

[Doa110]

is there any tricks/tips to memorzing the solubility of compounds?
thanks!

This is what I have:

Soluables.....................................Exceptions
______________________________________________________________
Group I.......................................Always soluble
NH4+ ........................................Always soluble
Nitrates......................................Always soluble
Acetates....................................Ag+
Cl-, Br-, I-..................................Ag+,Pb+,Cu+,Hg2+
Sulfate (SO4^2-).........................Ag+,Pb+,Ba+,Sr+,Ca2+

Insolubles ..................................Exceptions
______________________________________________________________
Carbonates................................w/Always solubles
Sulfites.....................................w/Always solubles
Phosphates................................w/Always solubles
Hydroxides, and Oxides................w/Always solubles and Ba+,Sr+,Ti+
Sulfides.....................................w/Always solubles and groupII

So when I'm memorizing, I call Ba+ ,Sr+, common elements because they make solubles, insolubles and vise versa!

The table has helped me. I hope it helps someone here too.

 

[kingcon9]

ALWAYS SOLUBLE (No exceptions to the rule)
Group 1A
NH4+
NO3-
C2H3O2-

SOLUBLE MOST OF THE TIME:
Middle of group 7A (Cl-, Br-, I-) is normally always soluble except for in H.A.P. (Hg22+, Ag+, and Pb2+)

SO42- (exceptions are Sr2+, Ba2+, Hg22+, Pb2+)

INSOLUBLES:
My little rhyme is:
S-OH
CO
PO

for
S2-, OH-, CO32-, and PO43-

[There are exceptions for each, but they're mostly in the "ALWAYS SOLUBLE"s list]

 

[polarmolar]

http://forums.studentdoctor.net/showthread.php?p=7018861 🙂

 

[supraman]

So increased branching means molecules can pack closer together, means they prefer the solid state, thus causing them to have a higher melting point. And since trans- geometric isomers can't pack as well as cis-, trans- will have a higher melting point. thus they will be solid more often than cis-. And this is why trans fats are bad for you - because they are solid and clog up arteries. Makes sense.
But boiling point does not depend on packing because the molecules are farther apart in solid. It is more dependent on intermolecular forces. Cis- will have net dipoles and thus have higher boiling points than trans. This also makes sense.

Best post I have ever read. (By Contach)