Question

Give reasons for the following:

Measurement of osmotic pressure method is preferred for the determination of molar masses of macromolecules such as proteins and polymers.

Answer 1

There are many reasons

1) Osmotic pressure can be measured at room temperature whereas other colligative properties need either high temp or low temp conditions.

2) Most of the macromolecules get denatured in high temp, this can be avoided.

3) Values of other colligative properties is very small that a small error can account to the large difference.

Answer 2

The osmotic pressure method has the advantage over other methods as pressure measurement is around the room temperature and the molarity of the solution is used instead of molality. Also as compared to other colligative property its magnitude is large even for dilute solution.