# bp elevation/fp depression

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#### puffylover

##### Full Member
10+ Year Member
7+ Year Member

so i understand the basics of this concept: add solute and bp is elevated and fp is depressed... but...

with this equation:
(delta)k=kim?

does saturation matter? for example, lets say that molality is really high and the solution is supersaturated...you still calculate with the high m? wouldn't the particles be stuck together in a crystal (thus not dissolved in the solvent)?

#### puffylover

##### Full Member
10+ Year Member
7+ Year Member
just to put my question into context, i was working on the TPR full length #5
Physical Science Section
Question #3

#### loveoforganic

##### -Account Deactivated-
10+ Year Member
it should only count for solvated compounds

#### BellJS

##### Full Member
so i understand the basics of this concept: add solute and bp is elevated and fp is depressed... but...

with this equation:
(delta)k=kim?

does saturation matter? for example, lets say that molality is really high and the solution is supersaturated...you still calculate with the high m? wouldn't the particles be stuck together in a crystal (thus not dissolved in the solvent)?

I believe these equations only apply to dilute and ideal solutions, please confirm?

In addition, although I don't have the question to which you are referring, the definition of supersaturation is such that the solute is dissociated and has not re-crystallized out of solution. If you are interested in determining the molality of a solution where more than enough solute has been added to reach saturation point, the extra solid that has not dissolved does not contribute to the molality of the solution.