Question

Inert pair effect is shown by:
A. s-block elements
B. p-block elements
C. d-block elements
D. f-block elements

Answer 1

First we must know about inert pair effects. Therefore, it is the property of two electrons in the outermost s-orbital to not be shared in post-transition elements.

Complete answer:
Let’s start with understanding the concept of the inert pair effect; inert pair effect is the property of two electrons in the outermost s-orbital to not being shared in post-transition elements. This term is often used to address the increasing stability of oxidation states that are two less than the group valency for heavier elements of the group 13, 14, 15, and 16.
Now, as written above this effect is shown by post-transition elements and by looking at periodic tables we know that after transition elements, elements of p-block comes so the answer will be p-block elements.
For a better understanding of the inert pair, effect let’s take an example, there is an element post the transitional d and f group, due to improper or we can say not so effective shielding effect of d and f orbital on s-orbital, the inert pair of s-orbital is held more tightly by the nucleus of the atom.
So, the answer to this question is B.

Note:
As one moves down the group the inert pair effect increases the stability of +1 oxidation state in group 13 elements increases. This can be shown by $A{l^ + } < {\text{ }}G{a^ + } < {\text{ }}I{n^ + } < {\text{ }}T{i^ + }$ out of these four ions the most stable one is $T{i^ + }$. The same is noted for group 14, 15 and 16 for oxidation states $+ 2,{\text{ }} + 3{\text{ }}and{\text{ }} + 4$ respectively.