The observed molar mass determined for $Na_2SO_4$ by the freezing point depression method is $50.0 \ g/mol$. The theoretical molar mass of $Na_2SO_4$ is $142 \ g/mol$. What will be the degree of dissociation $\alpha$ for $Na_2SO_4$ in water?

The van't Hoff factor $i$ for a compound which undergoes dissociation in one solvent and association in another solvent is respectively:

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)

For an $AB$ type ionic substance,which ratio of theoretical to experimental molecular mass is not consistent?

For a $0.1 \ M$ $Ba(NO_3)_2$ solution,the van't Hoff factor is $2.74$. The degree of dissociation is ....... $\%$.

$1.2 \ mL$ of acetic acid having density $1.06 \ g \ cm^{-3}$ is dissolved in $1 \ L$ of water. The depression in freezing point observed for this concentration of acid was $0.041^{\circ} C$. The van't Hoff factor of the acid is $(K_f \text{ of water } = 1.86 \ K \ kg \ mol^{-1})$