Starting with the energy level/shell closest to the nucleus electrons fill the different shells in order of increasing energy.
Shell 1 | Shell 2 | Shell 3 | Shell 4 |
——————————- Increasing Energy —————————–> |
Energy levels or shells can be divided into sub-shells, which can hold different numbers of electrons.
Shell 1 | Shell 2 | Shell 3 | Shell 4 | |||||||
Sub-Shell | s | s | p | s | p | d | s | p | d | f |
Within each sub-shell there are one or more orbitals. Each orbital can hold a maximum of two electrons (of opposite spin).
Shell 1 | Shell 2 | Shell 3 | Shell 4 | |||||||
Sub-Shell | s | s | p | s | p | d | s | p | d | f |
Number of orbitals in sub-shell | 1 | 1 | 3 | 1 | 3 | 5 | 1 | 3 | 5 | 7 |
Number of electrons allowed in each orbital | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
Total number of electrons in each sub-shell | 2 | 2 | 6 | 2 | 6 | 10 | 2 | 6 | 10 | 14 |
Explore the different atomic orbitals in 3D
s-orbitals | p-orbitals | d-orbitals