The stability of + 1 oxidation state increase in the sequence
A.
$$Al < Ga < In < Tl$$
B.
$$Tl < In < Ga < Al$$
C.
$$In < Tl < Ga < Al$$
D.
$$Ga < In < Al < Tl$$
Answer :
$$Al < Ga < In < Tl$$
Solution :
The given elements belong to third group. These elements mainly exhibit + 3 and + 1 oxidation states. As we know, the stability of lower oxidation state, increases on moving down a group due to inert pair effect. Thus, the sequence of stability of + 1 state is $$Al < Ga < In < Tl$$
Releted MCQ Question on Inorganic Chemistry >> P - Block Elements
Releted Question 1
The reddish brown coloured gas formed when nitric oxide is oxidised by air is