What is Electron Configuration? – Atomic Orbits, Representation

Do you know all the electrons in the elements are assigned into different atomic orbitals based on their configuration? And do you know that all the properties of the elements directly depend on the Electron Configuration? This means it is essential for the students to understand what Electronic Configuration is. To help you out, we have put together a detailed guide about Electron Configuration, Atomic Orbitals, and Electron Representation. 

What is Electron Configuration?

As stated above, Electron Configuration is defined as the distribution of electrons in different atomic orbitals of an element. Moreover, in order to represent the electron configuration of an element, an electron-containing subshell, along with the number of electrons in it, is shown as a sequence. For instance, in hydrogen, the electronic configuration is represented as 1s1.   

But not all element electron configurations can be represented in standard forms because of their length due to large atomic numbers. In such cases, an abbreviated notation is employed to describe electron configuration. And in this abbreviated notation, the atomic subshells of the noble gas electronic configuration are replaced by the noble gas symbols inside a square bracket. For example, the abbreviated electronic configuration of calcium is shown as,

\(Ar4 s^{2}\)

where Argon represents the

\(1 s^{2} 2s^{2}2p^{6}3s^{2}3p^{6}\)

Uses of Electronic Configuration

Now that we have a good understanding of the Electronic Configuration. Let us now talk about the various benefits or the importance of Electronic Configuration.  

  • To understand the atomic spectra of various elements, an electronic configuration is essential  
  • As explained above, the properties of the elements can only find out using electronic configuration 
  • Besides this, the valency of all elements directly depends on the number of electrons in an atomic orbital, which in turn is determined using electronic configuration 

How to represent Electronic Configuration?

Moving on to our next topic, how to write the Electronic Configuration for various elements. Regardless of the method, this process mainly depends on three main steps Shells, Subshells, and Notations.  


Firstly, in shells, the maximum no of electrons is accommodated based on the type of element and more importantly, on the principal quantum number(n). Thus, based on the shell, the principal quantum number varies. For instance, in the first shell, which is K, the principal quantum number n is 1. Below are some examples of shells and their principal quantum numbers. 

Shell  “n” value  Maximum electrons in the Shell 
K  1  \(2 n^{2}\) = 2
L  2  \(2 n^{2}\) = 8
M  3  \(2 n^{2}\) = 18
N  4  \(2 n^{2}\) = 32



Unlike the shells, the subshells are categorized with the help of the azimuthal quantum number (I). However, this quantum number is directly dependent on the principal quantum number (n). And therefore, based on the number of shells in an element, the subshells also vary. Therefore, the atoms in these shells are named, s, p, d, f.  For instance, 

  • The Element with principal quantum number n = 1, will observe an azimuthal quantum number value of I = 0, which is found in subshell 1s.  
  • For n = 2,  

                      I = 0, 1, 

                     Subshells = 2s, 2p. 

  • For n = 3,  

                     I = 0, 1,2 

                    Subshells = 3s, 3p, 3d. 

  • For n = 4,  

                     I = 0, 1,2,3 

                     Subshells = 4s,4p, 4d, 4f. 


The notations are basically the subshell labels, which include the subshells name, shell number as well as the electrons in the subshell (represented using superscript). For example, the electronic configuration of argon as stated above is

\(1 s^{2} 2s^{2}2p^{6}3s^{2}3p^{6}\)


With the help of the comprehensive details provided above, you will now be able to understand all about Electron Configuration, its functions, and how to represent Electronic Configuration. If you find any other similar topics from the chemistry subject harder to understand, then you can check out the online interactive classes offered by Tutoroot. At Tutoroot, we are geared towards helping you get the best ranks and scores in academics by providing classes that are interactive and easy to follow. 

Leave a Reply

Your email address will not be published.