Question

underline the valence electrons.
1s²2s²2p⁶3s²3p⁶4s¹
1s²2s²2p⁶3s²3p⁶4s¹
1s²2s²2p⁶3s²3p⁶4s¹
1s²2s²2p⁶3s²3p⁶4s¹

Explanation:

Valence electrons are the electrons in the outermost shell of an atom. In the electron configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}\), the outermost shell is the 4th shell, and the electron in it is \(4s^{1}\).

Answer:

\(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}\underline{4s^{1}}\) (the second option in the given choices)