While a great number of properties of solutions may depend on the relative amounts of solute and solvent, there is one class of 4 properties which are generally considered together because they depend on the number of solute particles dissolved in a given amount of solvent, and not on the identity of the solute. The identity of the solvent also matters, of course.

These properties are known as the colligative properties of solutions (collected properties) and they are:

vapor pressure lowering

boiling point elevation

freezing point depression

osmotic pressure elevation

Each of these solution behaviors has been used at some time for analytical purposes although generally only osmotic pressure is used that way today.