The observed and calculated molecular weights of calcium nitrate are $65.6$ and $164$ respectively. The degree of dissociation of calcium nitrate is .......... $\%$.

The values of observed and calculated molecular weight of silver nitrate are $90$ and $170$ respectively. The degree of dissociation of silver nitrate is ......... $\%$.

$A$ $0.5\%$ 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 $74.6\, g\, mol^{-1}$)

Explain abnormal molar masses.

Phenol associates in benzene to a certain extent to form a dimer. $A$ solution containing $20 \times 10^{-3} \ kg$ of phenol in $1 \ kg$ of benzene has its freezing point decreased by $0.69 \ K$. Calculate the percentage degree of association of phenol. ($K_f$ for benzene $= 5.12 \ K \ kg \ mol^{-1}$)

$2\,g$ of benzoic acid $(C_6H_5COOH)$ dissolved in $25\,g$ of benzene shows a depression in freezing point equal to $1.62\,K$. The molal depression constant $(K_f)$ for benzene is $4.9\,K\,kg\,mol^{-1}$. What is the percentage degree of association of the acid?