Freezing Point

[burke236]

Advertisement - Members don't see this ad

How do I solve this problem?

which of the following will possess the lowest freezing point?

A. 0.1 m Na3PO4
B. 0.1 m H2SO4
C. 0.1 m C6H12O6
D. 0.1 m NaCl

The answer is A, but I am not sure how you are supposed to know that.

 

[PiBond]

freezing point is a colligative property. therefore, the answer depends on the number of particles, not necessarily their identify. the van't hoff factor (i) is the number of ions a molecule dissociates into. the more molecules the more the freezing point depression.

Na3PO4 dissociates into 4 particles (I believe), while all the other dissociate into less. it helps that they're all in the same concentration