Entropy Ostwald

In the years following Berzelius, a number of further examples of catalytic action were discovered, but scientific appreciation of their mode of action had to await the arrival of experimental and theoretical techniques for the study of reaction rates. It then became possible for F.W. Ostwald to define a catalyst as a substance that increases the rate at which a chemical system approaches equilibrium, without being consumed in the process. This handy form of words encapsulates the essential truth of the catalytic effect, and has stood the test of time it carries with it a number of important implications that we should now explore. The first of these is that the position of equilibrium attained in a catalysed reaction is exactly the same as that which would ultimately be arrived at in its absence this must be so because the equilibrium constant K is determined by the Gibbs free energy of the process, and this in turn is fixed by the enthalpy and entropy changes, thus ... 

Ludwig Boltzmann, bom Vienna 1844. Ph.D. Vienna. Professor Graz, Vienna. Develcped the kinetic theory of gases independently of Maxwell (viz., Boltzmann constant s, k). Firm supporter of the atomic theory in opposition to Mach and Ostwald, helped develop concept of entropy S). Died Duino, Austria (now in Italy), 1906 (suicide incurred by depression). Inscribed on gravestone S = k log W. 

In some cases crystallisation sequences are observed where a first formed phase transforms after extended reaction times to other phases. This kind of behaviour is in accord with Ostwald s law, which states that under kinetically controlled conditions, the first phases to form will be those with higher entropy, and these may transform towards the thermodynamically most stable phase via phases with progressively lower entropy and lower free energy. The sequential synthesis of zeolite Na-Y and then the denser zeolite Na-P from the same... 

Jacobus van t Hoff, like Ostwald one of the founders of physical chemistry, dissociated himself from the use of abstract physical conceptions and mathematical functions, such as entropy, as is done by physicists hke Gibbs, Planck, and Duhem [1903, 24]. There is no mention of entropy anywhere in his massive three-volume textbook (1898-1900). But, then, van t Hoff also avoided other abstract mathematical functions, such as the Helmholtz function... 

To surmount the conceptual obscurity often associated with entropy, other authors did try to spell out what entropy was. One way to do this, especially for authors influenced by Ostwald s energetic manner of thinking, was to try to explain entropy increase as the dispersal of moveable energy. Here the idea was... 

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