The oxidation state and covalency of Al in [AlCl(H2O)5]2+ are respectively:
In aqueous solution. The water molecules are just interacting electrostatically, and not actually bonding. Their partially negative end is pulled by aluminum's + 3 oxidation state in an ion-dipole interaction. Cl − is similarly pulled by Al 's + 3 oxidation state
Oxidation state of Al in given compound x+(-1)+5(0) = +2 x = +3 while covalency is 6.