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Anonymous asked in Science & MathematicsChemistry · 1 month ago

What is the enthalpy?

Fe3O4 + 8HCl - 2FeCl3 +FeCl2 + 4H2O


and how do you solve for it

1 Answer

  • 1 month ago
    Favorite Answer

    What information do you have available to you? What have you just been discussing in class? Do you have a table with standard heats of formation? That is the easiest way to get to an enthalpy change for a reaction. So, for any reaction:

    Delta Hrxn = Sum of Delta H of formation of products - sum of Delta H of formation of the reactants. 

    For this reaction:

    Delta Hrx = 2(Delta Hf FeCl3) + Delta Hf FeCl2 + 4(Delta Hf H2O) - [Delta Hf Fe3O4 + 8(Delta Hf HCl)

    In this calculation, states matter, so you need to know whether you are dealing with aqueous HCl or HCl(g) and whether you form solutions and whether the water is H2O(l) or H2O(g). Hopefully you are provided that information and just didn't include it here.

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