posted by Jessie .
Can someone please help me with this question?
Could freezing point depression be used for substances that are not soluble in water?
Please help me....can you explain why? Is there anywhere I can find this information because my chemistry book doesn't have any info. about this! Thanks so much for the help ;-)
No, it could not be used. You have to have molecules of solute dispersed uniformly over the surface of the solution to achieve freezing point depression. If the material does not dissolve, you would have a colloidal mixture. Patches of ice would form at the normal freezing point.
It depends on what you mean. If you mean a solution not water based, for instance an organic dissolved in an organic substance, neither of which is soluble in water, the answer is yes, freezing point depression is a colligative property associated with vapor pressure reduction. See http://en.wikipedia.org/wiki/Raoult%27s_law
However, if you are thinking of a non water soluble substance added to water, drwls is correct, it wont work.