Nemst heat theorem

Because it is necessary to exclude some substances, including some crystals, from the Nemst heat theorem, Lewis and Gibson (1920) introduced the concept of a perfect crystal and proposed the following modification as a definitive statement of the third law of themiodynamics (exact wording due to Lewis and Randall (1923)) ... 

Because of the Nemst heat theorem and the third law, standard themrodynamic tables usually do not report entropies of fomiation of compounds instead they report the molar entropy 50 7 for each element and... 

Finally, it will be shown (Section 11.8) that the basic observation (5.77a) is already a consequence of inductive laws that were previously incorporated in the Gibbsian formalism. Thus, even the Nemst heat theorem and Fowler-Guggenheim unattainability statement (although meaningful and valid) are essentially superfluous, bringing no new content to the thermodynamic formalism. We therefore conclude that all formulations of the third law fail one or more of the above criteria, and thus play no useful thermodynamic role as addenda to the Gibbsian formalism. 

K5rber7 calculated (i) the density at 0°K. from the coefficient of expansion of the liquid at 1 atm. pressure, and (ii) the density at infinite pressure from the compressibility of the liquid at 0° to 50° C. and Tammann s equation, v=v ,- -AKI K- -p), where Ooo=volume at p=oo, and A and K are constants. The first value was somewhat smaller than the second, which was connected with the vanishing of do/dJ at 0°K. according to the Nemst Heat Theorem ( 73.H). The possibility of the compression of the molecules themselves must, however, be taken into account. 

In the absence of any interceding phenomena, it seems necessary only to allow the supercooled liquid longer and longer periods of equilibration to ensure that its entropy will fall below that of the crystal at the temperature Jk (denoted Fj and in Refs. 58 and 106, respectively). Such an occurrence, though not actually in violation of the third law at finite temperatures, would imply a contradiction of the Nemst heat theorem on the approach to 0°K. This seems unlikely and raises the question of the existence of a thermodynamic singularity underlying the glass transition at or above the Kauzmann temperature T. ... 

The third law of thermodynamics is claimed to be related to, but not dependent on, the second law of thermodynamics. It is also known as the Nemst heat theorem. The history of the third law has been reviewed by Hiebert and Kox [17, 18]. The third law was pubhshed by Nernst in 1906 [19]. Subsequently we cite from Nemsfs original paper ... 

The Third Law of thermod5mamics for large systems, also known as the Nemst heat theorem, state that the absolute zero temperature is rmattainable. Currently, the third law of thermod5mamics is stated as a definition the entropy of a perfect crystal of an element at the absolute zero of temperature is zero. This definition seems to be valid for the small systems as well as the large systems. 

Third Law of Thermodynamics (1906). Solutions and gases are excluded from the third law. The Nemst heat theorem, also identified as the third law of thermodynamics, was extended by Planck by adding the postulate that the absolute entropy of a pure solid or a pure liquid approaches zero at 0 K ... 

Since the entropy is S= - dFfdT dAJdTy the Nemst heat theorem (also called the third law of thermodynamics) can be expressed in the form ... 

Afjter much discussion of its range of validity, the Nemst heat theorem has l een stated in the form that the entropy of all factors within a system which are in internal thermodynamic equilibrium disappears at absolute zero temperature. Nemst s other work is considered later (see p. 633). 

Thermochonistry — The Thomsen-Berthelot Principle — Free Energy — Dissociation — Equilibrium and Heat of Reaction — The Nemst Heat Theorem — Dixon — Influence of Moisture on Chemical Changes — The Burning of Carbon Monoxide — The Combustion of Hydrocarbons — Luminosity of Flames — The Detonation Wave — Nemst—Haber. 

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