Which of the following aqueous solutions has the lowest freezing point?
A)1.5 m aluminum perchlorate.
B)1.0 m magnesium phosphate
C)1.5 m calcium nitrate
D)2.0 m potassium chloride

Question

Quizplus · Accepted Answer

Aluminum perchlorate, Al(ClO4)3, dissociates into four ions (one Al3+ and three ClO4-), which has the highest van't Hoff factor (i = 4) among the options. The freezing point depression is directly proportional to the van't Hoff factor and the molality of the solution, making the solution with aluminum perchlorate have the lowest freezing point.

Which of the Following Aqueous Solutions Has the Lowest Freezing