Examples of Conductors and Insulators

A material that readily transmits energy is a conductor, while one that resist energy transfer is called an insulator. There are different types of conductors and insulators because there are different forms of energy. Materials that conduct electrons, protons, or ions are electrical conductors. They conduct electricity. Usually, electrical conductors have loosely bound electrons. Materials that conduct heat are thermal conductors. Substances that transfer sound are acoustical conductors. There are corresponding insulators for each type of conductor.

Many materials are both electrical and thermal conductors or insulators. However, there are exceptions, so don't assume just because a sample conducts (insulates) ​one form of energy that it behaves the same for other forms! Metals typically conduct both heat and electricity. Carbon conducts ​electricity as graphite, but insulates as diamond, so the form or allotrope of a material can be important.

Examples of Electrical Conductors

Here are some examples of electrical conductors:

• silver
• aluminum foil
• gold
• copper
• graphite
• steel
• brass
• bronze

Examples of Electrical Insulators

• glass
• plastic
• rubber
• porcelain
• air
• pure water
• dry paper
• dry wood

Examples of Thermal Conductors

• diamond
• silver
• gold

Examples of Thermal Insulators

• polystyrene foam
• water
• mineral wool
• plastic