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

$1 \ mol$ each of the following compounds is dissolved in $1 \ L$ of solution. Which will have the largest $\Delta T_b$ value?

$5 \ g$ 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 observed molar mass of an electrolyte is always less than its calculated value because the value of the van't Hoff factor '$i$' is...

If the relative decrease in vapour pressure is $0.4$ for a solution containing $1 \, mol$ of $NaCl$ in $3 \, mol$ of $H_2O$,the degree of ionization of $NaCl$ is .......... $\%$.

An aqueous solution is prepared by dissolving $0.1 \ mol$ of an ionic salt in $1.8 \ kg$ of water at $35^{\circ} C$. The salt remains $90 \%$ dissociated in the solution. The vapour pressure of the solution is $59.724 \ mm \ Hg$. Vapor pressure of water at $35^{\circ} C$ is $60.000 \ mm \ Hg$. The number of ions present per formula unit of the ionic salt is . . . . . .