The observed and calculated molecular mass of silver nitrate $(AgNO_3)$ are $92.64$ and $170$ respectively. The degree of dissociation of silver nitrate is ........ $\%$.

$20 \ g$ of a binary electrolyte (molar mass = $100 \ g \ mol^{-1}$) is dissolved in $500 \ g$ of water. The freezing point of the solution is $-0.74 \ ^oC$. Given $K_f = 1.86 \ K \ kg \ mol^{-1}$,the degree of dissociation of the electrolyte is ......... $\%$.

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 $1.86 \ K \ kg \ mol^{-1}$).

$75.2 \ g$ of phenol is added to $1 \ kg$ of solvent. The depression in freezing point is $7 \ K$. If phenol undergoes dimerization,calculate the percentage of association. $(K_f = 14 \ K \ kg \ mol^{-1})$

Acetic acid dissolved in benzene shows a molecular mass of

Dimerisation of solute molecules in low dielectric constant solvent is due to