What is the effect of the addition of impurities on the freezing and boiling points of a substance?

Colligative property: They are the type of property that depends upon the concentration of solute and not on the type of solute.

Depression in the freezing point and elevation in the boiling point are types of colligative properties

Depression in the freezing point: The freezing point of a substance gets lower with the addition of impurity.

• For example, The addition of salt to ice lowers the freezing point of ice.

Elevation in the boiling point: The boiling point of a substance gets elevated with the addition of impurity.

• For example, The addition of salt to water elevates the boiling point of water.

So, the addition of impurities to a substance results in depression in the freezing point and elevation in the boiling point.