Which of the following is a non-electrolyte?

The elevation of boiling point of $0.10 \ m$ aqueous $CrCl_{3} \cdot xNH_{3}$ solution is two times that of $0.05 \ m$ aqueous $CaCl_{2}$ solution. The value of $x$ is.........
[Assume $100 \%$ ionisation of the complex and $CaCl_{2},$ coordination number of $Cr$ as $6,$ and that all $NH_{3}$ molecules are present inside the coordination sphere $]$

At $25 \ ^oC$,the highest osmotic pressure is exhibited by $0.1 \ M$ solution of

When $CuSO_4$ is added to a solution of ammonia,what happens to the colligative properties of the solution?

For the dissociation of $Na_2SO_4$,how is the degree of dissociation $\alpha$ used to calculate the van't Hoff factor $(i)$?

$A$ solution containing $10 \ g$ of an electrolyte $AB_2$ in $100 \ g$ of water boils at $100.52^{\circ} C$. The degree of ionization of the electrolyte $(\alpha)$ is............ $\times 10^{-1}$.
(nearest integer)
[Given : Molar mass of $AB_2 = 200 \ g \ mol^{-1}$,$K_{b}$ (molal boiling point elevation constant of water) $= 0.52 \ K \ kg \ mol^{-1}$,boiling point of water $= 100^{\circ} C$;
$AB_2$ ionises as $AB_2 \rightarrow A^{2+} + 2B^{-}$]