noble gases have 8 valence electrons. Beryllium, however, (Be, atomic number
4)—1s^22 s^2 —has 2 valence electrons. Oxygen—1s^22 s^22 p^4 —has 6 valence
electrons.
Remember:• Valence electrons are the electrons in the outermost energy
shell.• Atoms with 8 valence electrons have a stable octet. They’re
very stable and are often referred to as the noble gases.Now review the material on electrons, electron configurations, and the stable
octet, and try these questions. The answers can be found in Part III.