Comportement des électrons

Electrons are small subatomic particles with a negative electrical charge.

Because they are negatively charged, electrons are attracted to the positively charged nucleus. They occupy energy levels, called shells, around the nucleus. Each energy level contains smaller regions called orbitals, where electrons are most likely to be found.

Electrons closest to the nucleus occupy the first energy level, which has the lowest energy. This level contains only one orbital, and each orbital can hold up to two electrons. That’s why the first energy level can hold up to two electrons.

Additional electrons fill higher energy levels, which contain more orbitals and can hold more electrons.

Electrons in the outermost energy level are called valence electrons.

Valence electrons shape the properties of an element because they can be transferred or shared with other atoms. This transfer or sharing allows atoms to form ionic or covalent chemical bonds.