A certain salt $X,$ gives the following results.

$(i)$ Its aqueous solution is alkaline to litmus.

$(ii) $ It swells up to a glassy material $Y$ on strong heating.

$(iii)$ When conc. $H _{2} SO _{4}$ is added to a hot solution of $X,$ white crystal of an acid $Z$ separates out.

Write equations for all the above reactions and identify $X, Y$ and $Z$

The correct statements from the following are :

$(A)$ The decreasing order of atomic radii of group $13$ elements is $\mathrm{Tl}>\mathrm{In}>\mathrm{Ga}>\mathrm{Al}>\mathrm{B}$.

$(B)$ Down the group $13$ electronegativity decreases from top to bottom.

$(C)$ $\mathrm{Al}$ dissolves in dil. $\mathrm{HCl}$ and liberate $\mathrm{H}_2$ but conc. $\mathrm{HNO}_3$ renders Al passive by forming a protective oxide layer on the surface.

$(D)$ All elements of group 13 exhibits highly stable +1 oxidation state.

$(E)$ Hybridisation of $\mathrm{Al}$ in $\left[\mathrm{Al}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{3+}$ ion is $\mathrm{sp}^3 \mathrm{~d}^2$.

Choose the correct answer from the options given below:

The Lewis acid character of boron tri halides follows the order:

Explain atomic radius of elements of boron family. 

In the extraction of aluminium the electrolyte is