Step 1 :

Freezing point of water , where

is the change in temperature and ,

is the van t Hoff factor,

is the molality of the solution and

is the molality depression constant = .

Freezing point : .

for sodium chloride is 2.

Substitute and in above equation.

.

Freezing point of 1 molal aqueous sodium chloride solution is .

Step 2 :

Freezing point : .

for glucose is 3.

Substitute and in above equation.

.

Freezing point of 1 molal aqueous glucose solution is .

Step 3 :

Observe the above calculations.

1 molal aqueous sodium chloride has the lower Freezing point compare with 1 molal aqueous glucose.

Solution:

1 molal aqueous sodium chloride has the lower Freezing point compare with 1 molal aqueous glucose.