Question

how freezing point decrease with decrease in vapour pressure?

Answer 1

Dear student, The freezing point depression can be related to vapor pressure. Adding solute to a solvent will dilute the solvent molecules, and according to Raoult’s law, this leads to a decrease in vapor pressure. The vapor pressure of the solid and liquid forms must be the same at freezing point, because otherwise the system would not be at equilibrium, the lowering of the vapor pressure leads to the lowering of the temperature at which the vapor pressures of the liquid and frozen forms of the solution will be equal. Regards,