colligative properties definition of colligative properties in the Free Online Encyclopedia.

colligative properties, properties of a solution solution, in chemistry, homogeneous mixture of two or more substances. The dissolving medium is called the solvent , and the dissolved material is called the solute. A solution is distinct from a colloid or a suspension .
..... Click the link for more information. that depend on the number of solute particles present but not on the chemical properties of the solute. Colligative properties of a solution include freezing point (see freezing freezing, change of a substance from the liquid to the solid state. The temperature at which freezing occurs for a pure crystalline solid is called the freezing point and is a characteristic of the particular substance.
..... Click the link for more information. ), boiling point boiling point, temperature at which a substance changes its state from liquid to gas. A stricter definition of boiling point is the temperature at which the liquid and vapor (gas) phases of a substance can exist in equilibrium.
..... Click the link for more information. , osmotic pressure (see osmosis osmosis (ŏzmō`sĭs)
..... Click the link for more information. ), and solvent vapor pressure vapor pressure, pressure exerted by a vapor that is in equilibrium with its liquid. A liquid standing in a sealed beaker is actually a dynamic system: some molecules of the liquid are evaporating to form vapor and some molecules of vapor are condensing to form liquid.
..... Click the link for more information. . By measuring these properties and comparing them with the corresponding properties of the pure solvent, it is possible to determine the number of particles of solute present in the solution. If the mass of solute present is also known, the number-average molecular weight molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the atomic weights of the atoms making up the molecule.
..... Click the link for more information. can be calculated by dividing the mass of solute by the number of particles present to obtain the average mass per particle.

colligative properties [kə′lig·ə·div ‚präp·ərd·ēz]

(physical chemistry)

Properties dependent on the number of molecules but not their nature.