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Question
Why are metals good conductors of electricity whereas glass is a bad conductor of electricity? Give reason?
Solution
For a material to be a conductor, it has to have a reasonable number of free electrons (i.e. electrons that are loosely bound to there atoms).The more the number of free electrons available, the better it is as a conductor.Glass, for all practical purposes, has no free electrons in its crystalline structure, therefore, is an insulator. Whereas, metals have large number of free electrons in room temperature. Thus, metals are good conductors of electricity.
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