Which electrons are typically highest in energy and most involved in chemical reactions?

Which electrons are typically highest in energy and most involved in chemical reactions?

• A. Core electrons
• B. Valence electrons
• C. Inner-shell electrons
• D. Electrons in fully filled subshells

Answer: (B)

Valence electrons are the outermost electrons and have the highest energy compared with the core. They’re the ones most easily removed or shared to form bonds, so they drive chemical reactivity. Core electrons are held tightly by the nucleus and stay largely unchanged during reactions, while inner-shell electrons are even more tightly bound and not involved in bonding. Electrons in fully filled subshells are especially stable and not typically used in bond formation, so they don’t participate in reactions.

Valence electrons are the outermost electrons and have the highest energy compared with the core. They’re the ones most easily removed or shared to form bonds, so they drive chemical reactivity. Core electrons are held tightly by the nucleus and stay largely unchanged during reactions, while inner-shell electrons are even more tightly bound and not involved in bonding. Electrons in fully filled subshells are especially stable and not typically used in bond formation, so they don’t participate in reactions.