20 g hemoglobin in a 1 L aqueous solution $(\mathrm{A})$ at 300 K is separated from pure water by semi permeable membrane. At equilibrium the height of solution in a tube dipped in a solution (A) is found to be 80.0 mm higher than the tube dipped in water.

The molar mass of hemoglobin is $\_\_\_\_$ $\mathrm{kg} \mathrm{mol}^{-1}$. (Nearest integer)

(Given : $\mathrm{g}=10 \mathrm{~m} \mathrm{~s}^{-2}, \mathrm{R}=8.3 \mathrm{kPa} \mathrm{dm} \mathrm{K}^{-1} \mathrm{~mol}^{-1}$, density of solution $=1000 \mathrm{~kg} \mathrm{~m}^{-3}$ )

A non-volatile, non-electrolyte solid solute when dissolved in 40 g of a solvent, the vapour pressure of the solvent decreased from 760 mm Hg to 750 mm Hg . If the same solution boils at 320 K , then the number of moles of the solvent present in the solution is $\_\_\_\_$ . (Nearest integer)

[Given: boiling point of the pure solvent $=319.5 \mathrm{~K}$,

$\mathrm{K}_{\mathrm{b}}$ of the solvent $=0.3 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$ ]

Two liquids A and B form an ideal solution. At 320 K , the vapour pressure of the solution, containing 3 mol of $A$ and 1 mol of $B$ is 500 mm Hg . At the same temperature, if 1 mol of A is further added to this solution, vapour pressure of the solution increases by 20 mm Hg . Vapour pressure (in mm Hg ) of B in pure state is $\_\_\_\_$ . (Nearest integer)

The osmotic pressure of a living cell is 12 atm at 300 K. The strength of sodium chloride solution that is isotonic with the living cell at this temperature is ________ g L^-1. (Nearest integer)

Given : R = 0.08 L atm K^-1 mol^-1

Assume complete dissociation of NaCl

(Given: Molar mass of Na and Cl are 23 and 35.5 g mol^-1 respectively.)