Valence electrons are electrons that are in the outermost orbitals of an atom. In the periodic table the elements are divided into groups. All elements of the first main group have one valence electron. All elements of the second main group have two valence electrons. And so on:
- group 1 - 1 valence electron
- group 2 - 2 valence electrons
- group 13- 3 valence electrons
- group 14 - 4 valence electrons
- group 15 - 5 valence electrons
- group 16 - 6 valence electrons
- group 17 - 7 valence electrons
- group 18 - 8 valence electrons