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I Have A Question about FUSION!

  1. Apr 7, 2005 #1
    I Have A Question about FUSION! Please Help!

    I Have A Question about FUSION! Please Help!


    the reaction of H and F produces about 500 kj/mol of energy:

    how much energy is produced by the reaction of 2.0kg of H with 38 kg of F to produce 2 kmol of HF?

    i know the answer is 5.0x 10 to the exponent 5 kJ... but i'm not sure why...

    thanks for your time =D
  2. jcsd
  3. Apr 8, 2005 #2


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    Staff Emeritus
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    Heat of Formation

    This is a problem about the heat of formation, rather than fusion. In the context of chemistry, fusion usually refers to liquid to solid phase change.

    Heat of fusion is the energy required for melting solids to liquids.


    Now for the problem, which states heat of formation of HF is 500 kJ/mol.

    The reaction is H2 + F2 -> 2 HF + Q, where Q = 500 KJ/mol, is the heat of formation.

    You have 1 kmol of H2 and 1 kmol of F2, which yields 2 kmol of HF.

    To solve the problem, one needs to know the basis of the heat of formation, i.e. the energy per mole.
    Last edited by a moderator: Apr 21, 2017
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