In some of the reactions thallium resembles aluminium, whereas in others it resembles with group-I metals. Support this statement by giving some evidences.

In some of the reactions thallium resembles aluminium, whereas in othe

1.	In some of the reactions thallium resembles aluminium, whereas in others it resembles with group-I metals. Support this statement by giving some evidences.
Answer» Solution :Thallium belongs to GROUP 13 of the periodic table. The most COMMON oxidation state for this group is +3. HOWEVER, heavier members of this group also display the +1 oxidation state. This happens because of the inert pair effect. Aluminium displays the +3 oxidation state and ALKALI metals display the +1 oxidation state. Thallium displays both the oxidation states. THEREFORE, it resembles both aluminium and alkali metals. Thallium, like aluminium, forms compounds such as `TlCl_3` and `Tl_2O_3`. It resembles alkali metals in compounds `Tl_2O` and TlCl.