Question

How does the electronic configuration of an atom relate to its position in the Modern Periodic Table?

Answer 1

Hint: Take an element from one of the 4 blocks of the periodic table. Now write the electronic configuration for that element. Now notice the relation between the last electron of each atom to its position in the periodic table. This will give you an idea about the relevance and upon this, you can build your understanding and thus answer the question.

Complete step by step solution:
We will take one element from the s block of the periodic table for ease of calculation as suggested in the hint. The element taken into consideration is sodium.
The electronic configuration of sodium is as follows:
$1{{s}^{2}}2{{s}^{2}}2{{p}^{6}}3{{s}^{1}}$
From the above electronic configuration, we get the following information:
- Number of valence electrons of the atom
- Number of shells present
- Valency of the atom
The number of shells present will help to determine the period to which the element belongs to. The number of valence electrons helps to determine valency and thus the charge of the ion formed by the element.
The number of valence electrons and the last orbital in which electron is placed helps to determine the group number as well.
Thus, this is how the electronic configuration of an element helps to determine its position in the modern periodic table.

Note: It is important to know that although electronic configuration can help to determine the group and period of elements, it is not applicable to all elements. This is because all the f block elements belong to group 3 although the number of valence electrons is not the same. So, the position determination is applicable to all the elements of s, p and d block.