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Re: heat is still a noun



Here are some follow up remarks that Criag Bohren sent me regarding heat and
enthalpy. I would suggest taking a look at Bohren and Albrecht's book
"Atmospheric Thermodynamics" for futher details about his views on these
matters. He has written much more. In addition, the preface, discussion of
energy conservation, and water and its transformations chapter are gems.
Larry Woolf



"Various quantities that get the name "heats" are in fact
enthalpy differences. For example, "latent heat of vaporization" is an
enthalpy of vaporization. This is undeniably true and not because I said
so. The latent heat of vaporization (sublimation, fusion) is the difference
in enthalpy between two phases of the same substance at the same
temperature. Seems simple enough to me. Enthalpy is a well-defined
thermodynamic variable. I didn't define it. Nor did I suggest that heat be
redefined as enthalpy. What I did suggest is that terms such as latent
heat, heat of combustion, heat of solution, etc. be scapped. Like it or
not, these are all enthalpy differences and hence should be called such.
But this does not mean that I redefined heat as enthalpy. To the contrary,
I have argued that there is no such thing as "heat" (as a noun, as a
substance) and hence there is no need to define it all."