Question

A solution of glucose(molar mass = 180 g mol-1) in water has a boiling point of 100.20°C. Calculate the freezing point of the same solution. Molal constants for water Kf and Kb are 1.86 K kg mol-1 and 0.512 K kg mol-1 respectively.

Answer 1

Given:

Tb of glucose solution = 100.20°C

△Tb = Kb .m

m = 0.20/0.512

m = 0.390 mol/kg