Give reasons : Measurement of osmotic pressure method is preferred for the determination of molar masses of

As compared to other colligative properties, its magnitude is large even for very dilute solutions / macromolecules are generally not stable at higher temperatures and polymers have poor solubility / pressure measurement is around the room temperature and the molarity of the solution is used instead of molality.

Detailed Answer :

In osmotic pressure method, pressure is measured at room temperature and instead of molality, molarity of the solution is used. It is preferred for the macromolecules like proteins as they are unstable at high temperature and polymers have poor solubility. Also, due to their high molecular mass, the only colligative property which has a measurable magnitude is osmotic pressure. Therefore, osmotic pressure method is preferred.