Question

Diagonal relationship of elements is due to same:
(A) size
(B) mass number
(C) atomic number
(D) electron affinity

Answer 1

Hint: To solve this question, first we need to understand the concept of diagonal relationships.
- Diagonal relationship occurs in different ways in which the atomic properties vary across the period and along the group in the modern periodic table.

Complete Solution :
Let us first learn about the diagonal relationships of the elements in the modern periodic table.
Diagonal relationship-
- We have seen the relationships across the periods and along the groups commonly. But diagonal relationship is a modern concept which says that the elements in the s-block i.e. second and third period elements exhibit the same.
- This relationship is commonly observed between the diagonal elements from s-block i.e. Li and Mg, Be and Al, B and Si, etc. thus, this relationship exists between certain pairs of diagonally adjacent elements.
- The elements showing this special kind of relationship are meant to exhibit similar kinds of properties. For example, Boron and Silicon are semiconductors.
- The main reason to show such a diagonal relationship is that the elements have similar atomic or ionic sizes. Furthermore, similar electronegativity and polarising power also plays an important role in contributing for this kind of relationships.
Therefore, we can conclude that, diagonal relationship in elements is due to the same size of those elements.
So, the correct answer is “Option A”.

Note: Do note that option (B) and (C) can never be the answer as atomic number and mass number cannot be the same for the elements in nature.
- Also, along with the second and third period of s-block elements; p-block and s-block elements also show diagonal relationships.