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Standard Enthalpy Of Reaction

  1. Nov 17, 2011 #1
    http://en.wikipedia.org/wiki/Standard_enthalpy_of_reaction" [Broken] of reactants (ΔHfO).

    My question is, why?

    And I also know that I can find http://en.wikipedia.org/wiki/Standard_enthalpy_of_reaction" [Broken] (ΔHrO) by subtracting the bond energies of the reactants from the products. The result differs very little from the the first method.

    Also, why is that?
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Nov 20, 2011 #2
    My Answer to your First Question: The standard heat of formation of the reaction is like the "net" heat of the reaction which is "(final) minus (initial)", which is what that formula describes.
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