4.4 Electrons and the periodic table ( additional)

fluoresce

-Ability of a mineral to emit visible light when exposed to ultraviolet light (black light)

electron shells

An energy level representing the distance of an electron from the nucleus of an atom.

excited electrons

Electrons that jump energy shells.

electron configuration

The arrangement of electrons in an atom.

energy levels

The fixed energies an electron can have.

ground state

The lowest energy state of an atom.

valency

equal to the number of electrons that each atom needs to gain, lose or share to fill its outer shell