Metallic Bonding
Year 9 ⚛️ Particles & Structure Describe metallic bonding; explain conductivity, malleability and melting point.
🔩 Metallic Bonding
In a metal, outer electrons are released into a shared "sea" of delocalised electrons. Positive metal ions are held together by electrostatic attraction to this electron sea.
Model
$$\text{Metal} = \text{lattice of } M^{n+} \text{ ions} + \text{sea of delocalised electrons}$$⚡ Properties Explained
| Property | Explanation |
|---|---|
| Conducts electricity | Delocalised electrons move freely, carry charge |
| Conducts heat | Free electrons transfer kinetic energy rapidly |
| Malleable | Layers of ions slide; electron sea maintains bonding |
| High melting point | Strong electrostatic forces between ions and electrons |
🔧 Alloys
Alloys are mixtures of a metal with other elements. The different-sized atoms disrupt the regular lattice, making the alloy harder than the pure metal.
Steel (Fe + C) — harder than iron. Brass (Cu + Zn). Bronze (Cu + Sn). Solder (Pb + Sn).
Ready to test yourself? Click the Quiz tab above to practise questions on this topic!
Interactive Demonstration — Metallic Bonding
Visualise the electron sea model of metallic bonding.
Metal ions (blue circles) are arranged in a regular lattice, surrounded by a "sea" of delocalised electrons (yellow dots) that are free to move.
This explains: electrical conductivity (electrons carry charge), thermal conductivity (electrons transfer energy), and malleability (layers slide over each other).
🔩 Metallic Bonding Visualiser
Calculate resistivity and relate to metallic structure.