Metallic Bonding
Metallic Bonding
Basic Principle
- Metallic bonding refers to the electrostatic attraction between positive metal ions and delocalised electrons
- In a metallic bond, metals effectively lose their valence electrons, leading to the formation of a ‘sea’ of electrons that moves freely around the metal cations
Structure and Properties
- This structure explains many typically metallic properties such as high melting points (due to strong bonds), good electrical conductivity (free moving electrons), malleability and ductility (cations can slide over each other)
- Delocalised electrons also explain the high thermal conductivity of metals, as vibrations (thermal energy) can pass quickly through the structure
Mobile Electrons
- The ‘free’ or ‘delocalised’ electrons in a metal can move throughout the structure, leading to the property of electrical conductivity
- These mobile electrons originate from the outermost shell of the metal atoms; they are the valence electrons
The ‘Sea’ of Electrons
- This ‘sea’ of electrons gives rise to metallic properties such as malleability and ductility
- The ‘sea’ allows the metal ions to roll over each other into new positions without breaking the metallic bonds
Metallic Alloys
- Understanding of metallic bonding is crucial to understanding the properties of metallic alloys
- An alloy results when a different type of atom is introduced into the metallic structure, disrupting the regular arrangement of the metal ions and making the structure more robust
Remember that understanding the principles of metallic bonding will provide an essential foundation for further topics, including metallurgy, electrochemistry, semiconductor physics, and more.