The solution containing $18 \mathrm{~g} \mathrm{dm}^{-3}$ glucose (molar mass 180) in water and another containing $6 \mathrm{~g} \mathrm{dm}^{-3}$ of solute A in water boils at same temperature. What is molar mass of A ?

If $P_1$ partial pressure of a gas and $x_1$ is its mole fraction in a mixture, then correct relation between $P_1$ and $x_1$ is

Calculate van't Hoff factor (i) of 0.2 m aqueous solution of an electrolyte if it freezes at $-0.660 \mathrm{~K} .\left(\mathrm{K}_{\mathrm{f}}=1.84 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$

Vapour pressure of a pure solvent is 550 mm of Hg . By addition of a non volatile solute it decreases to 510 mm of Hg . Calculate the mole fraction of solute in solution.