Why do electrons influence an atom’s chemical behavior?

Electrons are the primary drivers of an atom’s chemical behavior because they occupy the outermost region of the atom, known as the valence shell. These valence electrons are more weakly attracted to the positive atomic nucleus than inner electrons, allowing them to be shared, lost, or gained when atoms interact with one another.312

The specific chemical properties of an element are determined by the number of electrons in this outermost shell. Atoms tend to react in ways that allow them to achieve a stable electronic configuration, often resembling that of a noble gas, which possesses a full valence shell. For example, elements with one electron in their valence shell, such as alkali metals, are highly reactive because they can easily lose that electron to reach a stable state.34

Ultimately, chemical bonding is a direct consequence of these valence electrons interacting, as the arrangement and pairing of electrons dictate how atoms combine to form compounds.24