Question

How is ΔT_b related to K_b for the substance whose molecular state changes in the solution?

Answer 1

When the molecular state of a solute changes in solution (due to association or dissociation), the relation between elevation in boiling point and the molal elevation constant is given by

ΔT_b = i . K_b . m

Here:

ΔT_b = elevation of boiling point

K_b = molal elevation constant (ebullioscopic constant)

m = molality of the solution

i = van’t Hoff factor, which accounts for the change in the number of solute particles due to association or dissociation.