Question

Group $13$ elements show $+1$ and $+3$ oxidation states. Relative stability of $+3$ oxidation state may be given as :

• A. $T{l}^{3+}>I{n}^{3+}>G{a}^{3+}>A{l}^{3+}>B^{3+}$
• B. $B^{3+}>A{l}^{3+}>G{a}^{3+}>I{n}^{3+}>T{l}^{3+}$
• C. $A{l}^{3+}>G{a}^{3+}>T{l}^{3+}>I{n}^{3+}>B^{3+}$
• D. $A{l}^{3+}>B^{3+}>G{a}^{3+}>T{l}^{3+}>I{n}^{3+}$

Answer 1

The correct option is B $B^{3+}>A{l}^{3+}>G{a}^{3+}>I{n}^{3+}>T{l}^{3+}$

Answer:- (B) $B^{+3}>{Al}^{+3}>{Ga}^{+3}>{In}^{+3}>{Tl}^{+3}$

Reason:-

As we move down the group the inert pair effect becomes more and more prominent which causes the decrease in stability of elements in +3 oxidation state.

Hence, (B) is correct answer.