A solution of the sugar mannitol (mol wt 182.2) is prepared byadding 54.66g of mannitol to 1000g of water. The vapor pressure ofpure liquid water is 2338 Pa at 200C. Mannitol isnonvolatile and does not ionize in aqueous solutions.
a. Assuming that aqueous mannitol solutions behave ideally,calculate the vapor pressure lowering (the difference between thevapor pressure of pure water and that of the solution) for theabove solution at 200C.
b. The observed vapor pressure lowering of the mannitol solutionabove is 12.40Pa. Calculate the activity coefficient (based on molefraction) of water in this solution.
c. Calculate the osmotic pressure of the mannitol solution ofpart (b) when it is measured against pure water and compare it withthe osmotic pressure of the ideal solution.
