Bound energy

high-resolution terminology - matching measurements at high-resolution

Bound energy

Description

The bound energy change in a closed system is that part of the energy change that is always bound to an exchange of heat,

∆B = ∆U - ∆A [Eq. 1]

∆B = ∆H - ∆G [Eq. 2]

The free energy change (Helmoltz or Gibbs; ∆A or ∆G) is the total energy change (total inner energy or enthalpy, ∆U or ∆H) of a system minus the bound energy change.

Therefore, if a process occurs at equilibrium, when ∆G = 0, then ∆H = ∆B, and at ∆_eW = 0 (∆H = ∆_eQ + ∆_eW; see energy) we obtain the definition of the bound energy as the heat change taking place in an equilibrium process (eq),

∆B = T∙∆S = ∆eQeq [Eq. 3]

Abbreviation: B [J]

History

• From Kubo 1976 North-Holland: "Free energy" is due to H. van Helmholtz (1882), and means that part of the internal energy that can be converted into work, as seen in the equation dF = dA for an isothermal quasi-static process. It was customary to call the remaining part, TdS, of the internal energy, dU = dF+TdS, the gebundene Energie (bound energy), but this is not so common now.

• IUPAC: Helmholtz energy, A = U - TS [J]
• http://www.eoht.info/page/On+the+Thermodynamics+of+Chemical+Processes 2018-12-27

• Recalling the term bound energy helps to resolve one of the historic battles in thermodynamics [2].

References

1. Kubo R (1976) Thermodynamics. An advanced course with problems and solutions. North-Holland Amsterdam, New York. -
2. Gnaiger E (1994) Negative entropy for living systems: controversy between Nobel Laureates Schrödinger, Pauling and Perutz. In: What is Controlling Life? (Gnaiger E, Gellerich FN, Wyss M, eds) Modern Trends in BioThermoKinetics 3. Innsbruck Univ Press: 62-70. - »Bioblast link«

MitoPedia concepts: Ergodynamics