Posted by Car on .
The freezing point of an aqueous solution of glucose was measured to be 1.52 oC. What is the osmotic pressure, in atm, of 100 mL of this solution at 25.0 oC? (Kf = 1.86 oC/m)
When I calculated it out I got 16.79 atm but the answer was wrong don't know what I messed up on.

CHM 152 
DrBob222,
If I use 1.52 = Kf*m I get something like 0.817 m for the concn of the glucose. If we assume molality is molarity (and with no density listed that's the best we can do), then pi = MRT = 0.817 x 0.08206 x 298 = 19.98 atm. Check my work.