consider two liquids A and B that form an ideal solution with ideal vapors. assume the normal freezing points of A and B are Ta= 250 K and Tb =300 K, respectively. Assume that the molar heats of fusion of A and B are equal and is 1 KJ/mole. If a solution of B containing a mole fraction of A, Xa, is cooled, eventually either A or B will freeze out of solution. If one desires to make the temperatures at which one of the two components freezes out solution as low as possible by adjustments of the Xa one can use the following expression: