Which of the following aqueous solutions has the highest boiling point,under identical conditions having a concentration of $0.03 \ m$?

$0.004 \ M \ K_2SO_4$ solution is isotonic with $0.01 \ M$ glucose solution. The percentage dissociation of $K_2SO_4$ is $........$ (Nearest integer).

$AB_2$ is $10\%$ dissociated in water to $A^{2+}$ and $B^{-}$. The boiling point of a $10.0 \text{ molal}$ aqueous solution of $AB_2$ is . . . . . . $^\circ C$. (Round off to the Nearest Integer). [Given: Molal elevation constant of water $K_b = 0.5 \text{ K kg mol}^{-1}$,boiling point of pure water $= 100^\circ C$]

$A^{2+}$,$B^{2+}$ and $C^{-}$ form an ionic complex like $A_{x-2}[B(C)_x]_2$. If the complex is $75 \%$ dissociated in a solvent with $i=4$,the coordination number of $B$ is:

When $Hg(CN)_2$ is added to a solution of completely ionized $KCN$,the following reaction occurs: $2KCN + Hg(CN)_2 \to K_2[Hg(CN)_4]$. Due to the formation of this complex,which of the following occurs?

The freezing point of one molal $NaCl$ solution,assuming $NaCl$ to be $100\%$ dissociated in water,is ............ $^oC$. (molal depression constant $= 1.86$)