If an Atom has 12 Electrons then if it is a Neutral atom then the Atomic Number of the Atom will be 12.
The Electronic Configuration of Element with Atomic Number 12 will be :
⇒ 1s² 2s² 2p⁶ 3s²
We can notice from the Electronic Configuration that :
Given atom has 2 electrons in the 1st shell.
⇒ In the Shell : n = 1
Number of Electrons = 2
In the similar way : Number of Electrons in 2nd shell = 2 + 6 = 8
⇒ In the Shell : n = 2
Number of Electrons = 8
In the similar way : Number of Electrons in 3rd shell = 2
⇒ In the Shell : n = 3
Number of Electrons = 2
