EVERYDAY SCIENCE

Detailed explanation-1: -Valence electrons are the electrons in the highest occupied principal energy level of an atom. In the second period elements, the two electrons in the 1s sublevel are called inner-shell electrons and are not involved directly in the element’s reactivity, or in the formation of compounds.

Detailed explanation-2: -Electrons in the outermost energy level of an atom are called valence electrons.

Detailed explanation-3: -Valence electrons are the electrons in the outermost shell, or energy level, of an atom. For example, oxygen has six valence electrons, two in the 2s subshell and four in the 2p subshell. We can write the configuration of oxygen’s valence electrons as 2s²2p⁴.

Detailed explanation-4: -The Group 5A elements have five valence electrons in their highest-energy orbitals (ns2np3).