chemistry
posted by Eric .
Assuming equal concentrations, rank these aqueous solutions by their freezing point.?
K2CO3, Li3PO4, Sn(ClO3)4, NH4I
I tried to rank them according to the number of ions but i can't get it.
highest freezing point > lowest freezing point
Sn(ClO3)4 > Li3PO4 > K2CO3 > NH4I but this wasn't correct. please help!
if anyone knows what it could be please help!

The solution with the greatest freezingpoint depression, ΔTf, will have the lowest freezing point. Freezingpoint depression is directly proportional to the total particle concentration. You need to compare the ions per formula unit.
From highest to lowest the order is...
NH4I, K2CO3, Li3PO4, and Sn(ClO3)4
NH4l has the lowest total particle concentration, the lowest ΔTf, and the highest (least negative) freezing point. Sn(NO3)4 has the highest total particle concentration, the highest ΔTf, and the lowest (most negative) freezing point. 
You reversed them....the one with the greater ions have a lower freezing point and the ones with less ions have a greater freezing point.

Let me know if this is correct :]

I'm scared D:

it was correct! what a stupid, unfortunate mistake =/ thanks for explaining it!

Why? Just compare the ions per formula unit. The ones with more ions have a lower freezing point and the ones with less ions have a greater freezing point. Trust me :) You just have to reverse your answers. The answer should be (from highest to lowest):
NH4I, K2CO3, Li3PO4, and Sn(ClO3)4 
Anytime! Glad to have helped.