Which of the following liquids will havethe lowest freezing point?

a. pureH2O
b. aqueous FeI3 (0.030 m)
c. aqueous glucose (0.050 m)
d. aqueous NaI (0.030 m)
e. aqueous CoI2 (0.030 m)

The liquid which ever releases the greatest number of particles  will have the lowest freezing point.

A) pure H2O  

B) Aqueous FeI3 (0.030m) releases 4X's = 0.120 mol/litre ions

C) aqueous glucose (0.050m) releases 0.050 moles/litre glucoes

D) aqueous NaI (0.030m) releases 2X's = 0.060 mol/ litre ions

E) aqueous CoI2 (0.030m) releases 3 X's = 0.090 mol/litre ions

The answer is  

B) Aqueous FeI3 (0.030m)