Find the expected value of $\Delta \mathrm{T}_{\mathrm{b}}$ for $1 \mathrm{~m} \mathrm{AlCl}{ }_3$ solution in water if solution of nonelectrolyte of same concentration has $\Delta \mathrm{T}_{\mathrm{b}}$ value ' $x$ ' K .

Calculate vapour pressure of pure volatile liquid $B$ at given temperature if mole faction of liquid $B$ and vapour pressure of pure volatile liquid $A$ are 0.4 and 400 mm Hg respectively.

$$ \left[\mathrm{P}_{\text {total }}=600 \mathrm{~mm} \mathrm{Hg}\right] $$

Calculate the molality of nonvolatile solution if solution freezes at $-0.95^{\circ} \mathrm{C}$

$\left[K_f\right.$ for water, $=1.86 \mathrm{~K} \mathrm{~mol}^{-1}$, freezing point of water $=0^{\circ} \mathrm{C}$ ]

Which of the following solutions exhibits highest freezing point depression?