Boiling points and molality Similar to the freezing-point depression, the boiling-point elevation
Delta Tb of a solution is quantitatively related to the molality m and the boiling-point-elevation
constant Kb of the solvent by the equation Delta Tb = Kb m where the boiling-point elevation is
the difference between the boiling points of the solution and the pure solvent. A solution of
water (Kb = 0.512 degree C/m) and glucose boils at 101.56 degree C. What is the molal
concentration of glucose in this solution? Assume that the boiling point of pure water is 100.00
degree C. Express the molal concentration numerically.
Solution
delta T = Kb x m => 1.56 = 0.512 x m => molality = 3.047 m
Delta Tb of a solution is quantitatively related to the molality m and the boiling-point-elevation
constant Kb of the solvent by the equation Delta Tb = Kb m where the boiling-point elevation is
the difference between the boiling points of the solution and the pure solvent. A solution of
water (Kb = 0.512 degree C/m) and glucose boils at 101.56 degree C. What is the molal
concentration of glucose in this solution? Assume that the boiling point of pure water is 100.00
degree C. Express the molal concentration numerically.
Solution
delta T = Kb x m => 1.56 = 0.512 x m => molality = 3.047 m
