Calculate the molality of the solution of nonvolatile solute if it freezes at $-0.36^{\circ} \mathrm{C}$.

$\left[K_{\mathrm{f}}\right.$ for solvent $\left.=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$

Calculate the vapour pressure of solution if relative lowering of vapour pressure and vapour pressure of pure solvent are 0.018 and 18 mm Hg respectively at 300 K .

Calculate the number of moles of nonvolatile solute dissolved in 0.5 kg solvent if molal elevation constant for solvent is $2 \mathrm{~kg} \mathrm{~K} \mathrm{~mol}^{-1} \left[\Delta \mathrm{T}_{\mathrm{b}}=0.8 \mathrm{~K}\right]$

Arrange the following equimolar solutions according to increasing order of osmotic pressure [Assume complete ionisation]

i) KCl

ii) $\mathrm{BaCl}_2$

iii) $\mathrm{AlCl}_3$

iv) $\mathrm{Al}_2\left(\mathrm{SO}_4\right)_3$