Acetic acid dissolved in benzene shows a molecular mass of

$A$ compound $MX_2$ has observed and normal molecular masses $65.6$ and $164$ respectively. Calculate the percentage of ionization of $MX_2$ ............ $\%$

Benzoic acid undergoes dimerization in benzene. $x \ g$ of benzoic acid (molar mass $122 \ g \ mol^{-1}$) is dissolved in $49 \ g$ of benzene. The depression in freezing point is $1.12 \ K$. If the degree of association of the acid is $88 \%$,what is the value of $x$? ($K_f$ for benzene $= 4.9 \ K \ kg \ mol^{-1}$)

The molecular weight of benzoic acid dissolved in benzene is found to be ............ $g/mol$.

$2$ molal solution of a weak acid $HA$ has a freezing point of $-3.885^{\circ} C$. The degree of dissociation of this acid is ........ $\times 10^{-3}$. (Round off to the Nearest Integer).
[Given: Molal depression constant of water = $1.85 \ K \ kg \ mol^{-1}$,Freezing point of pure water = $0^{\circ} C$]

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