Question

The relative stability of +1 oxidation state of group 13 elements follows the order:

• A. $Al<Ga<Tl<In$
• B. $Tl<In<Ga<Al$
• C. $Al<Ga<In<Tl$
• D. $Ga<Al<In<Tl$

Answer 1

The correct option is C $Al<Ga<In<Tl$

Due to the inert pair effect as we move down the group in ${13}^{th}$ group lower oxidation state become more stable.

So, the correct order is: $Al<Ga<In<Tl$.