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Homework Help: Basic Energy Question- Hot and Cold Water

  1. Jan 14, 2013 #1
    Why actually does "hot" water freeze before cold water? This sounds very basic but believe me I cant come up with a single feasible reason
  2. jcsd
  3. Jan 14, 2013 #2


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    Staff: Mentor

    You refer to teh so called Mpemba effect. The jury is still out on this one. Even if it happens it happens only sometimes, when some particular (and not well defined) conditions are meet.
  4. Jan 14, 2013 #3

    I like Serena

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    Homework Helper

    Mmh, interesting.
    Just looked up the Mpemba effect.
    Weird thing, there seems to be something missing in the wiki article.

    I know that water freezing can result in different ice structures (15 types).
    It would make a difference which ice structure water freezes in.
    When super cooled water freezes "wild" - no structure (amorphous solid water or ASW).
    This is how water occurs on other planets and moons.
    I imagine it takes less (loss of) energy to freeze that way.
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