Can't figure out part 2/3
1) If the osmotic pressure of a 3.62×10-2-M aqueous solution of Ca(NO3)2 was found to be 2.51 atm at 20°C, what would be the "observed" van't Hoff factor?
2.88
2) Use the above van't Hoff factor to predict the freezing point of this solution.
Note that the corresponding molality would be 3.65×10-2 m, given that the density of the solution is 0.997 g/cm3.
3) Use the above van't Hoff factor to predict by how many degrees the boiling point of this solution will be elevated above that for pure water.
1. pi = iMRT. pi = i*0.0362*0.0821*293 = 2.51
i = 2.88
2. dT = i*Kf*m
delta T = 2.88*1.86*0.0365
Then 0C - delta T = new freezing point.
3. dT = i*Kb*m = 2.88*0.512*0.0365