Answer: 0.35 m
> 0.20 m
>0.10 m
> 0.15 m
> 0.15 m 
Explanation:
Depression in freezing point:

where,
= freezing point of solution
= freezing point of solvent
= freezing point constant
m = molality
1. For 0.10 m 

, i= 4 as it is a electrolyte and dissociate to give 4 ions. and concentration of ions will be 
2. For 0.35 m 

, i= 2 as it is a electrolyte and dissociate to give 2 ions. and concentration of ions will be
3. For 0.20 m 

, i= 3 as it is a electrolyte and dissociate to give 3 ions. and concentration of ions will be
4. For 0.15 m 
, i= 1 as it is a non electrolyte and does not dissociate to give ions.
5. For 0.15 m 

, i= 2 as it is a electrolyte and dissociate to give 2 ions and thus have
As concentration is highest for 0.35 m
, freezing point depression will be highest and thus has lowest freezing point. As concentration is lowest for 0.15 m
, freezing point depression will be lowest and thus has highest freezing point