Can All Insulators be Charged?
Country: United Kingdom
Date: Winter 2012-2013
I have been asked by a student whilst teaching about electrostatics. Can you charge all insulator materials? If you can if you could charge a covalently bonded material i.e. dragging electrons from the hydrogen atoms in an organic molecule; why do they not become ions and then start reacting with other substances around them.
There is a big difference between storing static charge (free electrons) on the surface of a body and breaking or affecting bonds within the actual material itself.
Althouh you can deliver a truly attention getting shock with static electricity, all those shockingly active electrons are located on the surface of the body collecting the charge. More importantly they come from outside the body, not from within it. You need to shuffle your feet along the rug or rub the insulator with fur or cloth to collect those electrons. Were the electrons from the insulator itself, these electrons would have to move through the insulator to be available to charge paper, shock our younger sibling or the cat. This is, by definition not going to happen in an insulator.
Charging a body with static electricity will in no way break down bonds within the body. It is just too weak.
Hope this helps.
Thanks for the good question. Yes, you can charge an insulator. In fact, that is why there is static "cling" in our clothes when we remove them from the dryer. The clothes are insulators and are attracted to each other because they are charged. Generally, when one charges a material, there are few electrons added or removed. You are correct in that the charged molecules (ions) could react with other substances. However, these reactions are not typically observed in everyday life. (They are observed in the gas phase in mass spectrometry, but that is a story for another day.)
I hope this helps. Please let me know if you have any other questions.
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Update: November 2011