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    • Thread Starter

    I have various questions to ask regarding Energetics.

    1) When calculating the delta H (reaction) given the average bond enthalpies, is it okay to calculate it for the whole equation? I mean if you calculate it for the bonds that are not being broken and not being made, won't these end up just cancelling themselves out?

    2) Whats the difference in calculating the:-
    i) delta H (formation)
    ii) delta H (reaction)

    given the delta H (combustion). Won't these two just end up being the same?
    And would this just end up being the Sum of delta H (combustion for reactants) - Sum of delta H (combustion for products), taking into account the moles? If this is true, what is the point in setting up a Hess Cycle?

    • Thread Starter


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