1. Electron Configuration of Cobalt:
Cobalt (Co) has an atomic number of 27, meaning it has 27 electrons. Its electron configuration is:
* 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁷
2. Identifying Core Electrons:
* Core electrons are the electrons in the inner shells of an atom. They are not involved in chemical bonding.
* Valence electrons are the electrons in the outermost shell. They are involved in chemical bonding.
3. Determining Core Electrons for Cobalt:
* The first three shells (1s², 2s² 2p⁶, 3s² 3p⁶) are considered core electrons.
* The 4s² and 3d⁷ electrons are valence electrons.
Therefore, the core electrons in cobalt's electron configuration are:
* 1s² 2s² 2p⁶ 3s² 3p⁶
