Metal atoms are held strongly to each other by metallic bonding to form a giant lattice structure. In this lesson, we will learn about metallic bonding and the physical properties of metal.
What is metallic bonding?
Metallic bonding is the force of attraction between positive metal ions and the “sea of mobile electrons”.
In the metal lattice structure, metal atoms lose their outer electrons and become positively charged ions. The outer electrons are not part of any atom and they are free to move from one metal atom to another. These electrons are said to be delocalized. Hence, the metal lattice structure is described as a lattice of positive ions surrounded by a sea of mobile electrons.
What are the physical properties of metal?
Metals are good conductors of electricity.
The outer electrons that are freely moving in the lattice structure, allow the metal to conduct electricity.
Metals are good conductors of heat.
Heat energy is transferred easily by the mobile electrons in the structure.
Metals have high densities, melting and boiling points.
Atoms in a metal are packed tightly in layers and are held together by strong metallic bonds. A large amount of energy is required to break these strong metallic bonds. This accounts for the high melting and boiling points of metals.
Metals are malleable and ductile.
Malleable means a metal can be hammered into different shapes and ductile means a metal can be drawn into wires. When a force is applied to a metal, the layers of metal ions slide over each other. The metallic bonding is not disrupted.
*All pictures are taken from google*
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