Electrical Conductivity

Definition

Electrical conductivity is the ability of a material to conduct an electric current, which is determined by the movement of charged particles within that material. This property is essential for understanding how different types of solids, such as ionic, metallic, and covalent solids, behave when an electric field is applied. The nature of bonding and the arrangement of atoms in these solids significantly influence their conductivity.

5 Must Know Facts For Your Next Test

1. Ionic solids typically conduct electricity when melted or dissolved in a solvent, as this allows ions to move freely.
2. Metals are excellent conductors of electricity because they have a 'sea' of delocalized electrons that can move easily through the lattice.
3. Covalent solids usually do not conduct electricity as they lack free charges; their electrons are localized and tightly bound in covalent bonds.
4. Temperature can affect electrical conductivity; for most metals, conductivity decreases with increasing temperature due to increased atomic vibrations that scatter electrons.
5. The conductivity of materials is often measured in siemens per meter (S/m), providing a quantitative assessment of how well a substance conducts electric current.

Review Questions

• Compare and contrast the electrical conductivity of ionic and metallic solids, and explain the underlying reasons for their differences.
  • Ionic solids conduct electricity primarily when melted or dissolved in water, as this process frees the ions, allowing them to move and carry charge. In contrast, metallic solids are excellent conductors even in solid form due to the presence of free-moving electrons within their structure. The key difference lies in the nature of bonding: ionic solids rely on mobile ions while metallic solids utilize delocalized electrons that facilitate electrical flow.
• Evaluate how temperature influences the electrical conductivity of metals compared to covalent network solids.
  • In metals, increasing temperature typically leads to decreased electrical conductivity because thermal vibrations of the metal lattice impede the flow of electrons. Conversely, covalent network solids generally maintain low conductivity regardless of temperature since their electrons are tightly bound within covalent bonds and cannot move freely. Thus, while temperature fluctuations affect metals significantly, covalent network solids remain largely unaffected due to their inherent electronic structure.
• Assess the implications of electrical conductivity on the practical applications of ionic versus metallic solids in technology.
  • The electrical conductivity of ionic and metallic solids plays a crucial role in their technological applications. For instance, ionic solids are utilized in batteries and electrolytes due to their ability to conduct electricity when ionized. On the other hand, metals are widely used in wiring and electronic components where continuous conductivity is necessary. Understanding these properties enables engineers to select suitable materials for specific applications, ensuring efficient energy transfer and functionality in electronic devices.

Related terms

Ionic Bonding: A type of chemical bonding that occurs between oppositely charged ions, resulting in the formation of ionic compounds that can conduct electricity when dissolved in water or molten.

Metals:

Elements characterized by their ability to conduct heat and electricity well due to the presence of free-moving electrons in their structure.

Covalent Network Solids: Solids where atoms are bonded by covalent bonds in a continuous network, generally leading to poor electrical conductivity due to the lack of free-moving charged particles.