How does the stability of +1 and +3 oxidation states vary in group 13?

Why does the stability of + 3 oxidation state decrease on moving down the group 13 ?

How dould you account for the following : The stability of +5 oxidation state decreases down the group 15 of the periodic table.

The stability of +1 oxidation state increases in the sequence :

Name the three factors which determine the stability of a particular oxidation state in solution.

The relative satbility of +1 oxidation state of group 13 elements follow the order :

The relative satbility of +1 oxidation state of group 13 elements follow the order :

The +1 oxidation state in group 13 and +2 oxidation state in group 14 becomes more and more stable with increased atomic number. Explain.

Due to inert pair effect, the stability of +2 oxidation state increases on moving down the group 14. Why?

General oxidation state shown by group 13 elements is

The heavier members of 13 and 14 groups besides the group oxidation state also show another oxidation state. Down the group (darr) , the stability of higher oxidation state increases. This concept which is commonly called inert pair effect has been used to explain many physical and chemical properties of the element of these groups. Heavier members of group 13 exhibit oxidation state.