Which of the following properties depends on the number of solute particles?

Colligative properties are those which depend solely on the number of solute particles in a solution, rather than on the specific identities of those particles. This includes properties like boiling point elevation, freezing point depression, osmotic pressure, and vapor pressure lowering.

For instance, when a non-volatile solute is added to a solvent, the boiling point of the solvent increases because the presence of solute particles disrupts the formation of vapor above the liquid. The extent of this change is directly related to the number of solute particles; in other words, adding more solute will have a proportionate effect on the boiling point elevation.

This differentiates colligative properties from other types of properties such as thermodynamic, kinetic, and microscopic properties, which may depend on various factors like molecular structure, energy considerations, or other specific aspects of the substances involved. These other types of properties do not rely only on the quantity of dissolved particles but may include characteristics such as energy states or the physical behavior of individual molecules.