Of the following $0.10 \ m$ aqueous solutions,which one will exhibit the largest freezing point depression?

$5 \ g$ of $Na_2SO_4$ was dissolved in $x \ g$ of $H_2O$. The change in freezing point was found to be $3.82 \ ^oC$. If $Na_2SO_4$ is $81.5 \%$ ionised,the value of $x$ ($K_f$ for water $= 1.86 \ ^oC \ kg \ mol^{-1}$) is approximately .............. $g$ (molar mass of $S = 32 \ g \ mol^{-1}$ and that of $Na = 23 \ g \ mol^{-1}$)

The elevation in boiling point of a solution of $10 \ g$ of a binary electrolyte (of molecular mass $100$) in $100 \ g$ of water is $\Delta T_b$. Then,the value of $K_b$ for water is

$0.01 \ M$ solutions of $KCl$ and $BaCl_2$ are prepared in water. The freezing point of $KCl$ is found to be $-2 \ ^oC$. What is the freezing point of $BaCl_2$ if it is completely ionised? ............. $^oC$

Which one of the following is the ratio of the lowering of vapour pressure of $0.1 \ M$ aqueous solutions of $BaCl_2, NaCl$ and $Al_2(SO_4)_3$ respectively?

Molal depression constant for a solvent is $4.0 \, K \, kg \, mol^{-1}$. The depression in the freezing point of the solvent for $0.03 \, mol \, kg^{-1}$ solution of $K_2SO_4$ is .............. $K$ (Assume complete dissociation of the electrolyte).