Which term identifies elements that have a full valence electrons, making them stable and unreactive?

Which term identifies elements that have a full valence electrons, making them stable and unreactive?

• A. Halogens
• B. Noble Gases
• C. Molecules
• D. Compounds

Answer: (B)

Elements with a full valence shell are chemically stable and unreactive. Noble gases have complete outer electron shells, which means they don’t need to gain or lose electrons to become stable. That fullness gives them very low reactivity under normal conditions. Halogens, by contrast, have seven valence electrons and readily gain one to reach a full shell, making them highly reactive. Molecules and compounds describe how atoms bond and come together, not individual elements with full valence shells. So the term that identifies elements with full valence electrons and stability is noble gases.

Elements with a full valence shell are chemically stable and unreactive. Noble gases have complete outer electron shells, which means they don’t need to gain or lose electrons to become stable. That fullness gives them very low reactivity under normal conditions. Halogens, by contrast, have seven valence electrons and readily gain one to reach a full shell, making them highly reactive. Molecules and compounds describe how atoms bond and come together, not individual elements with full valence shells. So the term that identifies elements with full valence electrons and stability is noble gases.