Lithium Atom (Li)
* Atomic Number: 3 (meaning it has 3 protons and 3 electrons)
* Electron Configuration: 1s² 2s¹
* Core Electrons: 2 (the electrons in the 1s orbital)
* Valence Electrons: 1 (the electron in the 2s orbital)
Lithium Ion (Li+)
* Formation: Lithium loses its one valence electron to achieve a stable, noble gas configuration like helium (1s²).
* Electron Configuration: 1s²
* Core Electrons: 2 (the electrons in the 1s orbital)
* Valence Electrons: 0 (it has lost its only valence electron)
Key Points
* Core electrons are the electrons in the inner shells of an atom. They are generally not involved in chemical bonding.
* Valence electrons are the electrons in the outermost shell of an atom. They are involved in chemical bonding and determine an element's reactivity.
* When lithium loses its valence electron, it becomes a positively charged ion (Li+) with a full outer shell, making it more stable.
