solubility rules

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Are they worth the memorization?

i'm wondering the same thing, i also noticed that EK and TPR differ on their rules, anyone know the REAL rules for solubility. Thanks.

i don't know, because i noticed some inconsistencies myself. probably not important. whenever you see a solubility problem think common ion effect.

Kaplan has a long list of all the rules, but I could just never get my head around them. Too many exceptions to the rules to the point where ... are there any rules?

I'd say be familiar. There's no telling whether you could get a question or two that could easily be answered with knowledge of a couple rules. I forget them now, but my TPR book had a couple that were worth putting to memory.

I have the same issue...so many rules and exceptions. I get the drift and don't plan to memorize but reading them over 48 hrs before the exam could help retain in for the short term.

As I recall, MCAT solubility just came down to whether the molecule was charged or not. Charged = soluble in polar stuff; non-charged = soluble in non-polar stuff

You mean memorizing this?


Probably not worth it.

I'd go with this.

FWIW, YES! Memorize the solubility rules, but be aware that you get slightly different versions based on whether you are reading Kaplan, TPR, or etc. So, it's important to remember that the solubility rules are not a binary thing. It's a spectrum of solubilities, and where one person defines "insoluble" may not be the same as where another person defines "insoluble". You should definitely know the basic rules, and if you have time, learn exactly why: i.e. "A phosphate of X, Y, Z is soluble/insoluble because ____"

Also, I'd say know the really really obvious ones like all nitrates being soluble and pretty much all ammonium containing compounds and alkali compounds being soluble. Also, know common-ion effect as suggested about and how solubility constants read.

in EK Audio Osmosis they say that it's not needed, but they talk about it anyway.

If I recall correctly, there was one or two questions on previous AAMCs that dealt with solubility