Conventions Benson-Helgeson

Although straightforward, the G and H defined by the Benson-Helgeson convention do contain some excess baggage in the sense that they contain the entropies of the elements at Tj.,Pr, which are contributing nothing to the usefulness of the concept. In other words, equation (7.6) can be rewritten... 

We mentioned in Chapter 3 the two conventions used to define apparent properties, which are used as a form of formation from the element properties at temperatures above 298.15 K. The Benson-Helgeson convention was described there. The Berman-Brown convention, although the same for AH°, is different for AG°. 

Both the Benson-Helgeson and Berman-Brown conventions are in common use at the present time. Both are far more sensible than what we have called the standard formation from the elements convention, but there is little to choose between them. Hopefully, one will become dominant in the near future. 

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