Which compound listed below has the greatest solubility in water?

Question

CdCO3
Cd(OH)2
CaF2
AgI
ZnCO3

how can i tell which on to choose, no matter what compounds are listed?

Answer 1

All of these are insoluble compounds. You look up the Ksp of each and calculate the solubility from the Ksp you find. One very important note here: The question doesn't specify units for solubility so you may get different answers if you calculate solubility in moles/L versus grams/L.

Answer 2

YOU MEMORIZE the solubility rules. Make some flash cards, and get it done.

http://www.flashcardexchange.com/tag/solubility