Respuesta :
Answer is: other elements are stable with 8 electrons.
For example sodium has eleven electrons and lost one electron to obtain electron configuration of noble gas neon. ₁₁Na⁺ 1s²2s²2p⁶.
Chlorine has 17 electrons (seven valence electrons), chlorine gain one electron to obtain electron configuration of noble gas argon. ₁₇Cl⁻ 1s²2s²2p⁶3s²3p⁶.
For example sodium has eleven electrons and lost one electron to obtain electron configuration of noble gas neon. ₁₁Na⁺ 1s²2s²2p⁶.
Chlorine has 17 electrons (seven valence electrons), chlorine gain one electron to obtain electron configuration of noble gas argon. ₁₇Cl⁻ 1s²2s²2p⁶3s²3p⁶.
Having 8 electrons in their outermost level of energy, all these elements are stable. The number of electrons in the outermost level is simply called as valance. These are the electrons in the atom that interact and form the chemical bonds. The stability of the element is also determined by the valance.