This rule states that atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight valence electrons, resembling the stable electron configuration of noble gases.
Exceptions:
* Hydrogen and Helium: These elements only need two valence electrons for stability, as their outer shell is the first shell, which can only hold two electrons.
* Transition metals: These metals can have more than eight valence electrons due to the involvement of d-orbitals in bonding.
However, the octet rule provides a useful framework for understanding chemical bonding and reactivity for most elements.
