So I'm taking Thermodynamics I in university. I'm just doing the homework now, and there is something that i don't really understand.(adsbygoogle = window.adsbygoogle || []).push({});

To get the Enthalpy of formation for hematite (Fe2O3) at 1200K, I first integrated the constant pressure heat capacity function over the temperature range from 298K to 1200K, then added the heats of transformation across this temperature range. but now, at the end, should the enthalpy of formation at 298K be added to the number that i found?

=> integrating over from 298K to 1200K, and adding the heat of transformation for hematite: I got this number: 129300J/mol

=> ΔH of formation at 298K is given as -821300J/mol, should i add these two numbers together?

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# Homework Help: Hess's Law problem

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