Octet Rule

Definition

The tendency of main-group elements relevant to water chemistry to be most stable when their outermost shell holds eight electrons.

Noble gases such as neon already have complete octets and are chemically at rest, while most other elements fall short and sit in a higher-energy, unstable state. Oxygen, with six valence electrons, is two short of an octet and so reacts readily. The drive to complete the octet is what pushes atoms to bond, share, or transfer electrons.

Related concepts

Noble gases · Valence electrons · Bonding

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Part of The Blueprint of Water · 🧪 chemistry