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Temperature physical or chemical change

  1. Dec 17, 2016 #1
    If you Increase or decrease temperature and change states of matter, that's a physical change.

    But are there any circumstances where temperature can cause a chemical change? Like if increasing temperature could break the bonds between the atoms and separate them? And I don't mean a combustion reaction. I'm talking about just temperature change.

    And if temperature can cause chemical change, then what if you heat H2O to really high temperatures? Like super high temperatures, would it break up into H2 and O2?
    Last edited: Dec 17, 2016
  2. jcsd
  3. Dec 17, 2016 #2


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    Staff: Mentor

    That's purely nonsensical as stated. I guess what you mean is "are there any circumstances where change in temperature produces a chemical change".

    Yes. Water example is a good one.
  4. Dec 17, 2016 #3
    yeah thats exactly what i meant
  5. Dec 17, 2016 #4
    Every compound will dissociate at very high temperatures , the water you mention will become a mix , continually breaking apart and recombining ....

    At more manageable temperatures there is nitrogen dioxide ... at low temperatures it exists as N2O4 molecules warm it up and there will be more and more NO2 molecules

    At 150C it will decompose 2 NO2 → 2 NO + O2 ...cool it down and it recombines.
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