Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025
Definition
An electron shell is a grouping of electrons surrounding the nucleus of an atom in distinct layers. Each shell can hold a certain maximum number of electrons and determines the atom's chemical properties.
AP course connection
Topic 2.1: 2.1 Elements and Atoms: The Building Blocks of Matter
The electrons in the outermost shell of an atom, which determine how the atom interacts chemically with other atoms.
Chemical Bond: A lasting attraction between atoms that enables the formation of chemical compounds, often involving interactions between valence electrons