What's the unit of enthalpy?

Hey guys,

What is the unit of enthalpy in TFM please? I saw the documentation said J/mmol. The temperature in my simulation blew up using this unit. I could have the wrong enthalpy or I could have the wrong unit. Should I use J/mmol in my TFM model? Thank you!


Enthalpy should be in Joule, where in the documentation does it say J/mmol?

However the thermo database uses the ratio H/R where R is in cal/(mol.K)



Thank you Jeff! Sorry I should have said heat of reaction instead of the enthalpy. In the user manual it says Specify Heat of Reaction

Check this checkbox to optionally specify the user-defined heat of reaction for the currently selected reaction (Joules/kmol).

Is this J/kmol the correct unit? If it is, I am getting unphysical temperature for my reaction based on the enthalpy change provided by this paper. https://pubs.acs.org/doi/pdf/10.1021/jp205499e So iā€™m just trying to figure out if I understood the MFiX unit incorrectly or the paper incorrectly.


Yes, J/kmol is the correct unit for heat of reaction

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