Question
Illustrate elevation in boiling point with the help of vapour pressure temperature curve of a solution. Show that elevation in boiling point is a colligative property?
Solution
Answer:
ΔTb = T2 – T1
ΔTb ∝ m
ΔTb = Kb x m
Here m (molality) is the number of moles of solute dissolved in 1 kg of solvent and the constant of proportionality, Kb is called Boiling Point Elevation Constant or Molal Elevation Constant.
Since ΔTb depends on molality of solution and not on nature of solute, therefore, ΔTb is a colligative property.
