If the $O.P.$ (Osmotic Pressure) of $1 \ M$ solutions of the following compounds in water can be measured,which one will show the maximum $O.P.$?

Among the given solutions,which one has the highest boiling point under similar conditions?

The freezing point depression constant for water is $1.86 \, ^\circ C \, m^{-1}$. If $5.00 \, g$ of $Na_2SO_4$ is dissolved in $45.0 \, g$ of $H_2O$,the freezing point is changed by $3.82 \, ^\circ C$. Calculate the van't Hoff factor $(i)$ for $Na_2SO_4$.

Osmotic pressure of a $4.44\%$ solution of anhydrous $CaCl_2$ was found to be $16.42 \ atm$ at $27 \, ^\circ C$. What is the degree of dissociation of $CaCl_2$ in $\%$?

For $0.1 \ M$ solutions of the following electrolytes,the colligative property will follow the order:

If sodium sulfate $(Na_2SO_4)$ undergoes complete dissociation into its constituent ions in an aqueous solution,what will be the depression in freezing point $(\Delta T_f)$ when $0.01 \ mol$ of sodium sulfate is dissolved in $1 \ kg$ of water (in $K$)? (Given: $K_f = 1.86 \ K \ kg \ mol^{-1}$)