Question

What happens to the freezing point of water when non-volatile solute such as salt?
A.It increases
B.It decreases
C.t does not change
D.Salt water will not freeze

Answer 1

The freezing point is referred to the temperature at which the liquid state of the component changes to the solid state on cooling. The depression in freezing point also called as cryoscopic constant is defined as the colligative property of solutions that is directly proportional to the molality of the solution.

Complete step by step answer:
Freezing-point depression is defined as the decrease of the freezing point of a solvent on the addition of a non-risky solute. Examples consist of salt in water, alcohol in water, or the mixing of solids including impurities into a finely powdered drug. In all cases, the substance introduced/found in smaller amounts is taken into consideration the solute, at the same time as the authentic substance found in larger quantities is ideal because of the solvent. The resulting liquid solution or solid-solid combination has a lower freezing point than the natural solvent or strong because the chemical capacity of the solvent within the aggregate is decreased than that of the natural solvent, the distinction among the two being proportional to the herbal logarithm of the mole fraction.
Hence option (2) is the correct one.

Additional Information:
The freezing factor is the temperature at which the liquid solvent and strong solvent are at equilibrium, in order that their vapour pressures are equal. When a non-volatile solute is added to a volatile liquid solvent, the solution vapour strain could be decreased than that of the natural solvent. As a result, the solid will attain equilibrium with the answer at a lower temperature than with the natural solvent.

Note:
Non volatile means the solute which itself has a tendency to evaporate. The depression in freezing point is negative because the temperature of the solution is lower than that of the pure solvent. The Raoult law for non volatile solute is the vapor pressure of solution of non volatile solute is equal to vapor pressure of the pure solvent at that temperature multiplied by the mole fraction of the component.