What effects do solutes have on a solvent's freezing and boiling boints?

The effect of a solute on the freezing point and boiling point of a solvent is related to what is known as the colligative property. Upon addition of the solute, the freezing point will be lowered, and the boiling point will be increased. The magnitude of the change will depend on the solute and how many particles it forms upon dissolving, and on the nature of the solvent and the freezing/boiling point constant for that solvent.