Calculate the molality of solution if its depression in freezing point is 0.18 K . $\left[\mathrm{K}_{\mathrm{f}}=1.6 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$

Identify the correct statement from following properties.

Calculate van't Hoff factor of 0.15 M solution of electrolyte if it freezes at $-$0.5 K.

$$\left[\mathrm{K}_{\mathrm{f}}=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$$

Calculate the relative lowering of vapour pressure of solution containing 46 g of non volatile solute in 162 g of water at $20^{\circ} \mathrm{C}$. [Molar mass of nonvolatile solute $=46 \mathrm{~g} \mathrm{~mol}^{-1}$]