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Homework Help: How to calculate heat of combustion?

  1. Nov 1, 2008 #1
    1. The problem statement, all variables and given/known data
    Calculate the heat of combustion per mole of glucose(s), C6H12O6(s).

    This is the only information given. There is no Hess' law equations or any of the sort.

    2. Relevant equations

    3. The attempt at a solution
    I already know the answer is roughly -2813kJ/mole but I don't understand how to arrive to the answer with this little information. I would like to be given some sort of direction that could help me calculate to -2813kJ/mole.
  2. jcsd
  3. Nov 1, 2008 #2


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    Homework Helper

    Write the balanced equation for C6H12O6 + xO2 -> whatever
    Find how many bonds are broken/made
    Look up the bond energy
    A bit of arithmatic
  4. Nov 1, 2008 #3
    For what's it's worth, I agree with the above poster. Draw a Lewis Dot structure and figure out the bonds. Bond energy=delta H of reaction = Bonds broken (reactants) - Bonds formed (final products). You can look up these values online or in your textbook. =)
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