The observed molar mass of an electrolyte is always less than its calculated value because the value of the van't Hoff factor '$i$' is...

Which of the following is a non-electrolyte?

An aqueous solution is prepared by dissolving $0.1 \ mol$ of an ionic salt in $1.8 \ kg$ of water at $35^{\circ} C$. The salt remains $90 \%$ dissociated in the solution. The vapour pressure of the solution is $59.724 \ mm \ Hg$. Vapor pressure of water at $35^{\circ} C$ is $60.000 \ mm \ Hg$. The number of ions present per formula unit of the ionic salt is . . . . . .

What is the percentage of dissociation of a $0.011 \ m$ aqueous solution of $K_3[Fe(CN)_6]$ having a freezing point of $-0.063 \ ^oC$? (Given: $K_f = 1.86 \ K \ kg \ mol^{-1}$ for water)

The Van't Hoff factor for sodium phosphate would be

$17.4\% \ (W/V)$ solution of potassium sulphate (mol. $wt. = 174$) is isotonic with $4\% \ (W/V)$ aqueous solution of $NaOH$. If $NaOH$ is $100\%$ ionised,the degree of ionisation of potassium sulphate is $........... \ \%$.