Silicon (Si)
* Electronic Configuration: 1s² 2s² 2p⁶ 3s² 3p²
* Valence Electrons: The 3s² and 3p² electrons are the valence electrons.
* Unpaired Electrons: The 3p subshell has two electrons, and each p orbital can hold a maximum of 2 electrons. Since there are three p orbitals, the two valence electrons in the 3p subshell will occupy separate orbitals with their spins aligned in the same direction (Hund's rule). Therefore, silicon has 2 unpaired electrons.
Lithium (Li)
* Electronic Configuration: 1s² 2s¹
* Valence Electrons: The 2s¹ electron is the valence electron.
* Unpaired Electrons: Since the 2s orbital can hold two electrons, and there is only one electron present, it will be unpaired. Therefore, lithium has 1 unpaired electron.
