Question

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

Explanation:

Valence electrons are in the outermost shell. 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 option with \(4s^{1}\) underlined)