2.4.1 Bonding Continuum
Bonding isn't binary. It exist on a spectrum defined by electronegativity.
The Van Arkel-Ketelaar Triangle
We often simplify bonding into three distinct types: Ionic, Covalent, and Metallic. In reality, there is a continuum. The Bonding Triangle allows us to predict the bonding type using average electronegativity () and the difference ().
Interactive Van Arkel-Ketelaar Triangle
Explore the bonding continuum. Click on a zone to learn more.
Click on a zone in the triangle to see details about that bonding type.
X-Axis: Average Electronegativity
- Low : Electrons held loosely (Metallic).
- High : Electrons held tightly (Covalent).
Y-Axis: Electronegativity Difference
- Low : Electron sharing (Covalent/Metallic).
- High (>1.8): Electron transfer (Ionic).
The Three Zones
Ionic
Top Vertex
Ex: CsF (Brittle, Insulator)
Metallic
Bottom Left
Ex: Na, Cs (Conductive, Malleable)
Covalent
Bottom Right
Examiner Tip: Intermediates
Compounds on the borders show intermediate properties. For example, Silicon falls in the "Semiconductor" zone on the base line. Silicon Carbide () sits on the border between Covalent and Metallic, explaining its hardness and semi-conductivity.