Question

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

Answer 1

Modern periodic law states that the physical and chemical properties of elements are periodic functions of their electronic configuration.

hence by electronic configuration we can identify which period and group an element belongs to it.

for example: Magnesium - atomic number 12

electronic configuration is 1s2 2s2 2p6 3s2.

so it is s block element.

group number - no of valence electrons- 2

period number - maximum principal quantum- 3

so Magnesium position is 3 Rd period and group second

Answer 2

1⃣ To know its position in periodic table first we should know the electronic configuration of the element. 

2⃣ For example Oxygen. Atomic number of Oxygen is 16Electronic configuration of oxygen - 2 8 6. Valence electrons:  The electrons, which are present in the outermost shell of an atom are called valence electrons.

3⃣ For any element number of valence electrons is equal to its group number. Here oxygen contains 6 valence electrons hence, it belongs to VI A group. 

✌️For any element the valence shell number  is equal to its period number. In oxygen 3rd shell is the outermost shell (Valence shell) hence, it belongs to period 3.