Water: A Conductor or Insulator?

Discussion in 'General Science' started by mavchick43, Oct 15, 2012.

  1. mavchick43

    Thread Starter New Member

    Oct 15, 2012
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    Hello All,

    I am confused as to why pure water is considered a poor conductor (insulator) of heat while dirty water is considered a good conductor of heat. Can someone please provide an explanation?

    Thank you.
    :)
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    The answer is in ionization. When something is ionized, it is usually short electrons, and so becomes a conductor. Ultra pure water, also known as DI (deionized) water is an insulator. Add a little table salt and the conductance (ability to carry current) increases dramatically.

    Gases heated until they are glowing are also ionized (such as reentering space vehicles), the glowing air is very conductive indeed.
     
  3. WBahn

    Moderator

    Mar 31, 2012
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    While Bill was talking about electrical conductivity, there is a general correlation between things that are good (or bad) electrical conductors and things that are good (or bad) thermal conductors and for the same reasons. But this is not universal and there are examples, such as diamond, where a very good electrical insulator is also a very good thermal conductor. This is because there are multiple ways for materials to conduct both electricity and heat and while some of them overlap, not all of them do.
     
  4. HonT

    New Member

    Oct 25, 2012
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    Can you describe what you mean by "dirty"? What exactly is the composition of the "dirty" water?
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    Whatever is in it. It is not clean. Since it is a solvent, it is by definition usually ionized.

    This one is a no brainer, so why the question?
     
  6. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    Show us some supporting data.
     
  7. loosewire

    AAC Fanatic!

    Apr 25, 2008
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    The age old story,if it less positive,it is more negitive, but still positive.
     
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