Octet rule

Definition

The octet rule states that atoms tend to form bonds in such a way that they achieve eight electrons in their valence shell, gaining a stable electron configuration similar to noble gases. This rule is fundamental for understanding molecular structures and chemical bonding.

5 Must Know Facts For Your Next Test

1. Atoms will gain, lose, or share electrons to fulfill the octet rule and achieve stability.
2. Elements in periods 2 and beyond often follow the octet rule strictly, while some exceptions exist for elements with d-orbitals.
3. Covalent bonds are formed when atoms share electrons to complete their octet.
4. Ionic bonds result from the transfer of electrons between atoms to satisfy the octet rule.
5. Lewis structures are used to represent molecules and illustrate how atoms fulfill the octet rule.

Review Questions

• What does the octet rule state about atomic stability?
• How do covalent and ionic bonds relate to the octet rule?
• Why might elements beyond period 2 not strictly follow the octet rule?

Related terms

Valence Electrons:

Electrons located in an atom's outermost shell that are involved in chemical bonding.

Lewis Structure:

A diagrammatic method for representing the arrangement of valence electrons among atoms in a molecule.

Noble Gas Configuration: A stable electron arrangement where an atom has a complete valence shell, similar to noble gases like neon or argon.