Which of the following solutions will have the highest boiling point?

At higher altitude,the boiling point of water is $95\,^oC$. The amount of $NaCl$ added to $1\,kg$ of water $(K_b = 0.52\,K\,kg\,mol^{-1})$ in order to raise the boiling point of the solution to $100\,^oC$ (assume $90\%$ ionisation of $NaCl$) is .......... $g$.

Calculate the van't Hoff factor $(i)$ of a centimolar solution of potassium ferrocyanide $(K_4[Fe(CN)_6])$ if it is $60\%$ dissociated at $300\text{ K}$.

The osmotic pressure of a dilute solution of an ionic compound $XY$ in water is four times that of a solution of $0.01\, M\, BaCl_2$ in water. Assuming complete dissociation of the given ionic compounds in water,the concentration of $XY$ (in $mol\, L^{-1}$) in solution is

$A$ compound contains $1.08 \ mol$ of $Na, 0.539 \ mol$ of $Cu$ and $2.16 \ mol$ of $F$. Its aqueous solution shows osmotic pressure which is three times that of urea having the same molar concentration. The formula of the compound is:

The freezing point of a $0.05 \ m \ BaCl_2$ solution in water ($100 \%$ ionisation) is about $(K_f = 1.86 \ K \ kg \ mol^{-1})$. (in $^oC$)