Electron arrangement of the first 20 elements
The table below shows the electron arrangement for the first 20 elements in the Periodic Table along with their Atomic number and symbols:
| Element | Electrons diagram and configuration |
|---|---|
1 H hydrogen |
 1 |
2 He helium |
 2 |
3 Li lithium |
 2.1 |
4 Be beryllium |
 2.2 |
5 B boron |
 2.3 |
6 C carbon |
 2.4 |
7 N nitrogen |
 2.5 |
8 O oxygen |
 2.6 |
9 F fluorine |
 2.7 |
10 Ne neon |
 2.8 |
| Element | Electrons diagram and configuration |
|---|---|
11 Na sodium |
 2.8.1 |
12 Mg magnesium |
 2.8.2 |
13 Al aluminium |
 2.8.3 |
14 Si silicon |
 2.8.4 |
15 P phosphorus |
 2.8.5 |
16 S sulfur |
 2.8.6 |
17 Cl chlorine |
 2.8.7 |
18 Ar argon |
 2.8.8 |
19 K potassium |
 2.8.8.1 |
20 Ca calcium |
 2.8.8.2 |