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  1. Jul 13, 2008 #1

    I realize that to calculate heat being released and contained during nuclear reaction you must understand the difference between its product mass and reactant mass by using *E=mc2.* My Question pertains to the heat being released during a chemical reaction... Is Mass conserved in this chemical reaction? , and if so where is its energy coming from?
  2. jcsd
  3. Jul 13, 2008 #2


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    Science Advisor
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    Welcome to PF!

    Hi WhiteRhasta ! Welcome to PF! :smile:

    Mass is conserved in chemical reactions.

    The energy differences result from the electrons being "shared" by different atoms, and therefore being in orbits with different energy levels …

    but all the energies are electromagnetic. :smile:
  4. Jul 13, 2008 #3


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    Mass _and_ energy are conserved together. So in the case of exothermical chemical reaction mass of products (after cooling) will be smaller then mass of reactants. However, change in the mass is so small, that we can safely treat it as if it is mass conservation only.
  5. Jul 14, 2008 #4
    Thanks tiny - tim, and Borek very much for that. That will surely assist me with an experiment I am conducting... Its nice to be a part of the physics community...
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