How does the addition of a solute affect the freezing point of a solution compared to the pure solvent?

When a solute is added to a pure solvent, the phenomenon known as freezing point depression occurs. This is a colligative property, which is dependent on the number of solute particles present in a solution rather than the identity of the solute.

As the solute dissolves in the solvent, the solute particles disrupt the formation of the orderly crystalline structure needed for the solvent to freeze. Consequently, a lower temperature is required to achieve the same level of order that leads to freezing. Therefore, the presence of a solute causes the freezing point of the solution to be lower than that of the pure solvent.

In summary, the addition of a solute results in a solution that has a lower freezing point compared to the pure solvent, affirming that the correct answer is indeed that the freezing point is lower than that of the pure solvent.