Electrons are actually held in Subshells within Shells.
Sub-shells > Shells > Orbitals
So starting from basic to complex:
- Shells are the big "Circle" or "Orbit" around the element.
- Sub-shells are smaller shells that form the big Shells.
- The number of Subshells in a Shell = The number of the shell.
- For example, Shell 3 (n=3) has 3 sub orbitals.
- Subshells come in different capacities.'S' can hold 2 electrons.
'P' can hold 6 electrons.
'D' can hold 10 electrons.
'F' can hold 14 electrons.
- Orbitals are the very small thing. A part of a subshell. There is a maximum of 2 electrons held in each orbital.
In summary, this is the hierarchy of electronic configuration of Sub-shells:
For example (Putting this into use)
The electronic sub-shell configuration of Gold:
1s2, 2s2, 2p6, 3s2, 3p6, 3d10, 4s2, 4p6, 4d10, 4f14, 5s2, 5p6, 5d10, 6s1
Where as the first number (Before the letter) is the Energy Level.
Where as the second number (After the letter) is the Number of Electrons held in the subshell.
Putting it into order to make it look tidy:
The things this can tell us: