Electronic structures

The electronic structure of an atom is a description of how the electrons are arranged. It can be shown as numbers or as a diagram.

Lithium atom with three electrons orbiting the nucleus: two in the first energy shell, one in the second.Electronic structure of lithium

Take lithium for example. The diagram shows each shell as a circle around the nucleus, with each electron represented by a dot. The electronic structure for lithium is written as 2.1 (showing that lithium atoms have three electrons, two in the first shell and one in the second shell).

Table showing the diagram, electron configuration and periodic table group of fluorine, neon, sodium and calcium.