In which of the following solutions are ions present?

The osmotic pressure of a $0.1 \ M$ solution of $NaCl$ and $Na_2SO_4$ will be:

$A$ solution containing $0.85 \ g$ of $ZnCl_2$ in $125.0 \ g$ of water freezes at $-0.23 \ ^\circ C$. The apparent degree of dissociation of the salt is ($K_f$ for water $= 1.86 \ K \ kg \ mol^{-1}$,atomic mass: $Zn = 65.3$ and $Cl = 35.5$)

Mark the correct relationship between the boiling points of very dilute solutions of $BaCl_2$ $(t_1)$ and $KCl$ $(t_2)$,having the same molarity.

Which of the following aqueous solutions has the highest freezing point?

$A$ $0.1 \ mol$ of a binary electrolyte undergoes complete dissociation in $250 \ g$ of a protic solvent. If the elevation in boiling point is $1.5 \ K$,the molal elevation constant $(K_b)$ is ............. $K \ kg \ mol^{-1}$.