CHEMISTRY GLOSSARY

Valence electrons are electrons that can be actively involved in a chemical change, usually electrons in the outermost (valent) shell. For example, sodium’s ground state electron configuration is 1s² 2s² 2p⁶ 3s¹; the 3s electron is the only valence electron in the atom. Germanium (Ge) has the ground state electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p²; the 4s and 4p electrons are the valence electrons.