Conductors and Insulators
From our understanding of Chemistry we know that electrons are arranged differently in different atoms. Some atoms hold their electrons very tightly making it difficult for the electrons to move (or electricity to be conducted). Other atoms hold their electrons loosely making it easier to move the electrons (conduct electricity).
Materials that allow the electrons to move are called conductors. These materials will allow the electricity to pass through them. These materials are usually metals (found in the d block of the periodic table). Materials that do not allow electrons to move (or not move alot) are called insulators. These are materials like plastic, and air. We know that air is an insulator because when electricity is turned on near us the electricity does not travel to us. |
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There is another classification of materials called Semi-conductors. Semi-conductors usually act as an insulator under normal conditions. When they are cooled down to very low temperatures the properties of these materials change so that they now conduct electricity. These materials have useful industrial applications as the flow of electricity can be controlled.
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