Chemistry: molality and freezing point?
posted by Agatha on .
What mass of ethylene glycol C2H6O2, the main component of antifreeze, must be added to 10.0 L water to produce a solution for use in a car's radiator that freezes at 23.3C?
Assume the density for water is exactly 1g/mL.
m = moles solute / kg solvent
Help please?

Silly meee!! This question is already answered. :)

I must have worked this problem six times (or more) in the last three days. Three today. Good luck. If you're reading this one note that might help. Instead of going through all the steps that I outlined, there is a short cut that is very useful.
The original way is
delta T = Kf*m
solve for m.
m=mols/kg.
solve for mols.
mols = g/molar mass.
solve for grams.
Here is the shortcut.
delta T = Kf*m
kgsolvent*m*molar mass = grams.
Hope this helps.
neat, huh?