Explanation:
In [tex]AlCl_{3}[/tex] compound, three chlorine atoms are attached to an aluminium atom.
Since atomic number of aluminium is 13 and it has three extra electrons. So, it donate single electron to each chlorine atom.
Therefore, octet of chlorine gets complete.
As, three chlorine atoms are attached to aluminium so, name of [tex]AlCl_{3}[/tex] is aluminium trichloride.