In a solvent,$50\,\%$ of an acid $HA$ dimerizes and the rest dissociates. The van't Hoff factor of the acid is $.....\times 10^{-2}$. (Round off to the nearest integer)

If $0.15 \ m$ aqueous solution of $KCl$ freezes at $-0.51^{\circ} C$,calculate the van't Hoff factor of $KCl$ (cryoscopic constant of water is $1.86 \ K \ kg \ mol^{-1}$).

If $0.1 \ M$ solution of $NaCl$ is isotonic with $1.1 \ w \%$ urea solution, the degree of ionisation of $NaCl$ is $($Molar masses of urea and $NaCl$ are $60 \ g \ mol^{-1}$ and $58.5 \ g \ mol^{-1}$, respectively.$)$

The values of observed and calculated molecular mass of silver nitrate are $92.64$ and $170$ respectively. The degree of dissociation of silver nitrate is ........ $\%$.

The observed osmotic pressure of a solution of benzoic acid in benzene is less than its expected value because:

$A$ $0.5\%$ solution of potassium chloride was found to freeze at $-0.24^{\circ} C$. The percentage dissociation of potassium chloride is .... (Nearest integer)
(Molal depression constant for water is $1.80\, K\, kg\, mol^{-1}$ and molar mass of $KCl$ is $74.6\, g\, mol^{-1}$)