Calculate the molality of solution of non volatile solute having depression in freezing point 0.93 K and cryoscopic constant of solvent $1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$.

A solution of non volatile solute is obtained by dissolving 2 g in 50 g benzene. Calculate the vapour pressure of solution if vapour pressure of pure benzene is 640 mmHg at $25^{\circ} \mathrm{C}$. [mol. mass of benzene $=78 \mathrm{~g} \mathrm{~mol}^{-1}$, mol. mass of solute $\left.=64 \mathrm{~g} \mathrm{~mol}^{-1}\right]$

What is Henry's law constant of a gas if solubility of gas in water at $$25^{\circ} \mathrm{C}$$ is $$0.028 \mathrm{~mol} \mathrm{~dm}^{-3}$$ ?

[Partial pressure of gas $$=0.346 \mathrm{~bar}]$$

A solution of nonvolatile solute is obtained by dissolving $$15 \mathrm{~g}$$ in $$200 \mathrm{~mL}$$ water has depression in freezing point $$0.75 \mathrm{~K}$$. Calculate the molar mass of solute if cryoscopic constant of water is $$1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$$.