Colligative properties are properties of solutions that depend primarily on the quantity of solute particles present in the solution rather than the nature or identity of those particles. This means that colligative properties such as boiling point elevation, freezing point depression, vapor pressure lowering, and osmotic pressure are influenced by the number of solute molecules or ions in a specified amount of solvent.
For instance, when a solute is dissolved in a solvent, it affects the physical properties of the solvent in a manner that depends on the concentration of solute particles. The more particles that are added, the greater the effect on these properties, regardless of whether the solute is an ionic compound that dissociates into multiple ions or a molecular compound that does not dissociate.
In contrast, other options focus on factors that do not determine colligative properties. The nature of the solute refers to its specific chemical characteristics, which do not influence the extent of the property changes as long as the number of particles is held constant. The temperature of the solution and the molecular weight of the solvent can affect various aspects of a solution, but they do not play a role in the definition or calculation of colligative properties. Therefore, the key factor remains the number of sol