What term describes the arrangement of electrons in an atom?

The term that accurately describes the arrangement of electrons in an atom is "electronic configuration." This refers to the specific distribution of electrons across the various energy levels and sublevels within the atom. Understanding electronic configuration is crucial because it provides insight into how electrons occupy different shells and subshells, which directly influences an atom’s chemical properties and reactivity.

For instance, the electronic configuration helps explain why certain elements exhibit similar chemical behavior, as those with similar configurations (particularly in their outermost shells) often belong to the same group in the periodic table. This concept is foundational in chemistry as it underpins principles such as bonding, ionization energy, and electronegativity.

Other terms, while related, do not specifically capture the electron arrangement as precisely as electronic configuration. "Atomic structure" refers more broadly to the composition of an atom, including protons and neutrons in addition to electrons. "Electron shell" indicates the layers where electrons reside but does not detail how they are distributed among the shells. "Molecular arrangement" pertains to how atoms are bonded and arranged in molecules, not just within individual atoms. Thus, electronic configuration is the most appropriate term for describing the arrangement of electrons in an atom.