The highest energy level in an atom is occupied by the valence electrons. These electrons are located furthest from the nucleus and possess the greatest energy.
Understanding Energy Levels in Atoms
Atoms have electrons arranged in different energy levels or shells. As you move further away from the positively charged nucleus, the energy of these levels increases.
- Lower Energy Levels: Electrons closer to the nucleus are more strongly attracted and have lower energy. The lowest energy level is often called the ground state. (Quora)
- Higher Energy Levels: Electrons in outer shells are less tightly bound and possess higher energy. (LibreTexts) These are the valence electrons. (Study.com, [Valence Electrons Reference])
The energy level isn't a fixed number; it's related to the atom's electron configuration and can vary across the periodic table. However, the valence shell consistently represents the highest occupied energy level in a neutral atom. When an atom absorbs energy (like a photon), a valence electron can jump to an even higher, temporarily occupied energy level. (Webb Telescope) This excited state is unstable, and the electron quickly returns to a lower energy level.
Ionization Level
It's important to note that the highest possible energy level is the ionization level. This is the energy required to completely remove an electron from the atom, effectively ionizing it. While valence electrons are at the highest occupied level in a neutral atom, the ionization level represents a state beyond the typical energy levels. (Chegg)
