Question

which of the following liquids have the highest freezing point?

a- aqueous Fe(NO3)3 (0.030)
b- aqueous glucose (0.050 m)
c- aqueous NaI (0.030 m)
d- aqueous NaI (0.010 m)
e- pure water


please explain the concept behind it as well thank you!

Answer 1

delta T = i*Kf*m
You want the one that has the smallest delta T since that will give you the highest freezing point/
All you need to do is to evaluate i*Kf*m
Kf is a constant so you can ignore that.
Evaluate i*m for each. But if you do all of that you're wasting your time.
Pure water freezes at 0 C. Right? All of the solutions freeze lower than 0 C. Right? So which is the highest freezing point?

Answer 2

so water would have the highest freezing point?

it wouldn't be aqueous NaI at 0.010 m ? i thought that lower concentration means higher freezing point, or is that only if they are all the same compound ?