Anhydrous $AlCl_3$ cannot be obtained from which of the following reactions?

Draw the structures of $BCl_3.NH_3$ and $AlCl_3$ (dimer).

Aluminium is a self-protecting metal,because

Given below are two statements:
Statement $I$: Aluminium is more electropositive than thallium as the standard electrode potential value of $E^\circ_{Al^{3+}/Al}$ is negative and $E^\circ_{Tl^{3+}/Tl}$ is positive.
Statement $II$: The sum of first three ionization enthalpies of boron is very high when compared to that of aluminium. Due to this reason,boron forms covalent compounds only and aluminium forms $Al^{3+}$ ion.

The number of water molecules present in borax,kernite and bauxite respectively are

The alloy formed from aluminum is ............ .