Take sodium as an example. Sodium has 11 electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons.. It has:
2 electrons in the first shell
8 electrons in the second shell
1 electron in the third shell
You can write sodium’s electronic configurationThe order electrons are arranged in different shells. with numbers and commas: 2,8,1
The electronic configuration of sodium can be shown in a diagram. The dots represent electrons. Electrons may be shown using dots or crosses.
Figure caption,
A diagram of the electronic configuration of an atom of sodium.