Question

Why does nacl solution freeze at lower temperature than water, but boil at higher temperature than water?

Answer 1

Explanation:

When non volatile solids are added eg-nacl to water. Boiling point increases and melting point decreases. It is because the number of water molecules available to become vapourise/freeze decreases due to impurity. ... As a result, the solution freezes at a lower temperature and boils at a higher temperature.

Answer 2

Answer:

Upon adding a non-volatile solute like NaCl to water, the vapor pressure is lowered. The vapor pressure of this solution becomes equal to that of pure solid solvent which is the freezing point of the solution occurs at a lower temperature. Thus freezing point of NaCl solution is lower than that of pure solvent.