Q2.15 An aqueous solution of non-volatile solute exerts a pressure of 1.004 bar at the normal boiling point of the solvent. What is the molar mass of the solute?
It is given that of aq. solution. This means 2 g of non-volatile solute in 98 g of H2O.
Also the vapour of water at normal boiling point = 1.013 bar.
Using Raoult's law :
So we get :
Thus the molar mass of non-volatile solute is 41.35 unit.