Question

Which of these solutions has the highest freezing point?



1.0 M molecular sucrose (C12H22O11)



1.0 M ionic sodium chloride (NaCl)



1.0 M ionic calcium bromide (CaBr2)



1.0 M ionic aluminum bromide (AlBr3)



1.0 M ionic potassium chloride (KCl)

Answer 1

Since all of them equimolar solution, finding Vant'Hoff factor (number of ions) requires to calculate the freezing point.
delta T = m x kf x i

i = Vant'Hoff factor ( numbers of ions dissolved in the solution)

The solution with more the number of ions will be having the highest freezing point.

Vant'Hoff factor for AlBr3 is 4 and KCl is 2. You can solve yourself now!