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In metals, the arrangement of atoms creates a unique bonding structure: metallic bonding. This type of bonding is characterized by a 'sea' of delocalized electrons. Delocalized electrons are not bound to any specific atom, allowing them to move freely throughout the metal lattice.

This movement of electrons is crucial for several metal properties. Here are some important characteristics of metallic bonding:

• Conductivity: The free-flowing electrons enable metals to conduct electricity effectively.
• Strength: The electrostatic attraction between metal cations and delocalized electrons contributes to the strong and stable structure of metals.
• Malleability and Ductility: The layers of atoms can slide over each other without breaking the metallic bond, making metals malleable and ductile.

Understanding these properties helps in real-world applications, such as why we use metals for electrical wiring.

Ionic bonding forms the backbone of ionic salts, which include everyday compounds like table salt. This bonding occurs between oppositely charged ions: positive cations and negative anions.

When a metal atom loses an electron, it becomes a positively charged ion, or cation. When a non-metal atom gains that electron, it becomes a negatively charged ion, or anion. The resultant attraction between these oppositely charged ions forms strong ionic bonds.

The structure of ionic compounds has distinct features:

• Lattice Structure: Ionic compounds often form a highly structured lattice, contributing to high melting and boiling points.
• Brittleness: The rigid ionic lattice can easily break if stress is applied, which accounts for the brittleness.
• Conductivity in Solution: Ionic compounds conduct electricity when dissolved in water or melted, due to ions being free to move and carry electric current.

These characteristics are central to the usability of ionic compounds in various chemical and physical processes.

Electrical conductivity is an important physical property that distinguishes materials based on their ability to allow electricity to flow through them. This characteristic can be greatly influenced by the type of bonding present in the material.

In metals, conductivity is high because of the presence of delocalized electrons that move freely and carry electrical current efficiently across the entire structure. This is the reason metals are commonly used as electrical conductors.

For ionic salts, conductivity varies depending on their physical state. They do not conduct electricity in solid form because the ions are fixed within the lattice and cannot move. However, when ionic compounds are dissolved in water or melted, the ions are freed from the lattice structure, enabling them to move freely and conduct electricity.

Key points regarding conductivity include:

• Metals can conduct electricity in both solid and liquid states due to delocalized electrons.
• Ionic Salts conduct electricity only when melted or dissolved in a solution, as this frees the ions.

Understanding electrical conductivity aids in choosing materials for specific electrical applications.