What are valence electrons?

Valence electrons are the electrons located in the outermost shell of an atom. These electrons play a crucial role in chemical bonding and reactions because they are involved in the formation of bonds with other atoms. An atom's ability to bond with others, whether through sharing (as seen in covalent bonds) or transferring (as seen in ionic bonds), is determined by the number of valence electrons it has.

While other options touch on concepts related to electrons, they do not accurately describe valence electrons. The innermost shell, for example, does not contain the valence electrons, as these are specifically found in the outermost shell where they can interact with electrons from other atoms. Understanding that valence electrons are the key players in chemical bonding helps clarify why this choice is the correct one.