DONNAN 



ART. A 



various authors are shown in Table 1, whilst the corresponding 

 names are given in Table 2. 



TABLE 2 



Names of Quantities 



Quantity 



2 

 3 



4 



Names employed 



Absolute Temperature. Temperature on the Kelvin (ther- 

 modynamic) scale. 



Energy. Total internal Energy. 



Entropy. 



Total Heat (term used by engineers). Heat Function for 

 constant pressure (Gibbs). 



Heat Function (Partington; Sackur; Milne). 



Heat Content (Lewis and Randall; Noyes and Sherrill). 



Enthalpy (Kamerlingh Onnes). 



Available Energy (Clerk Maxwell). 



Free Energy (Helmholtz). Isothermal Potential (Helm- 

 holtz). Internal Thermodynamic Potential (Duhem). 



Free Energy (Planck; Lorentz; Sackur; Partington; Schott- 

 ky, Ulich and Wagner; most European authors since Helm- 

 holtz). 



Work Content (Noyes and Sherrill). Work Function (Milne). 



Helmholtzian Free Energy (Guggenheim). 



Thermodynamic Potential at constant Pressure (Duhem). 



Free Energy (Lewis and Randall; Noyes and Sherrill; many 

 authors, American and European, following the lead of the 

 American School of chemical thermodynamics created by 

 Noyes and Lewis). 



Thermodynamic Potential (Lorentz; Sackur; Partington). 



Gibbs' Thermodynamic Potential (Schottky, Ulich and 

 Wagner) . 



Gibbs' Free Energy (Guggenheim). 



Notes to Tables 



(a) Gibbs, using i^ to denote 5, called —\p the "Force Function for 

 Constant Temperature." 



(b) Massieu called his functions i/' and \p' the "Characteristic Func- 

 tions" of the system. 



(c) It will be noted that Planck's function * is identical with Mas- 

 sieu's function \J/'. 



(d) As regards nomenclature used at the present time, it is to be 

 noted that both the quantities 5 and 6 are called Free Energy. This is a 

 source of confusion to students of thermodynamics. Similar remarks 

 apply to the use of the symbol F, which may denote either 5 or 6. 



