What are colligative properties? Write the colligative property which is used to find the molecular mass of macromolecules.

Colligative properties are those properties of a solvent which depend on the no. of solute particles relative to total no. of particles present in the solution and not on their nature.

Such colligative properties exhibited by solution are relative lowering of vapor pressure (RLVP) of a solvent, elevation in boiling point, depression in freezing point of solution and osmotic pressure.

The colligative property which is used to find the molecular mass of macromolecules such as proteins, polymers, etc is osmotic pressure of solution because of following reasons-

• The pressure measurement is done at room temperature as such macromolecules are stable at room temperature.

• Concentration of solution is expressed in molarity.

• The magnitude of is large even for very dilute solution.