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In metal lattices....
- Electrons leave the outer shell of metal atoms. These 'delocalised' electrons are now free to move around metal ions.
- Positively charged metal ions are formed since metal atoms lose electrons. Metal ions are fixed in position.
- Most metals are solids at room temperature, so the metal ions are closely packed in a regular pattern to form giant metallic lattice structure.
👇 2D diagram of a metallic lattice 👇
Metallic bonding
- Strong electrostatic attraction between positively charged metal ions and negatively charged electrons
- Keeps metal atoms strongly held to each other
For IGCSE Chemistry, you should be able to explain the properties of metals based on the lattice structure.
Properties of Metals
1. High melting and boiling point
- Giant metallic lattice consists of many strong metallic bonds.
- A lot of energy is required to break up the numerous bonds during melting and boiling.
- Thus, the melting and boiling point of metals is high.
2. Good electrical conductivity
- When voltage is applied to a metal, delocalised electrons can move in one direction.
- The movement of the electrons make up an electrical current.
3. Malleable and ductile
- When force is applied to a metal, layers of metal ions can slide over each other.
- This does not break metallic bonding.
- Thus, metals are strong but flexible.