Metallic Bonding

This lesson explains metallic bonding and how the structure of metals accounts for their characteristic properties. You also need to understand why alloys are harder than pure metals. This topic is covered in the Edexcel GCSE Chemistry (1CH0) specification under Structure, Bonding and Properties.

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What Is Metallic Bonding?

In a metal:

• The atoms are arranged in a regular pattern (a lattice).
• The outer-shell electrons of each metal atom are delocalised — they are no longer associated with a single atom.
• This creates a structure of positive metal ions (the atoms that have lost their outer electrons) surrounded by a "sea" of delocalised electrons.
• The metallic bond is the strong electrostatic attraction between the positive metal ions and the delocalised electrons.

Exam Tip: The definition of metallic bonding is: "the strong electrostatic attraction between positive metal ions and a sea of delocalised electrons." Learn this word for word.

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The Structure of Metals

The structure can be described as: