Catalytic force

In 1836 Jons Jakob Berzelius considered eight seemingly unrelated experimental results and concluded that there was a common thread among them. The commonality he defined as catalysis. In doing tliis, Berzelius proposed that a catalytic force was responsible for catalytic action. The concept of catalysis is today considered by most researchers to be due to Berzelius, probably because of the popularity of his annual Handbook of Chemistiywhere he published his definition of catalytic action. For the next one hundred years many referred to the phenomenon as contact catalysis or contact action, as proposed by Mitscherlich. 

Berzelius Definition of catalysis, catalyst, catalytic force... 

In 1835 Berzelius coined the term catalysis to describe the influence of certain substances on the nature of diverse reactions, the substances themselves apparently being unchanged by the reaction. He imbued these materials with a catalytic force capable of awakening the potential for chemical reaction between species that would normally be nonreactive at a given temperature. In more modern terms the following definition is appropriate. 

Berzehus, in 1839, had interpreted fermentation as caused by a catalytic force. He postulated that a body by its mere presence could, by affinity to the fermentable snbstance, canse its decomposition to the products. 

The United Nations Environment Programme (UNEP) works to protect public health and the environment worldwide. UNEP Chemicals is the focus for all of UNEP s activities, and the main catalytic force in the UN system for concerted global action on the environmentally sound management of hazardous chemicals. 

The first observations of an increase of the reactivity between gases in the presence of a metal were made, almost one hundred years ago, by chemists like Davy or Thenard. This pioneer work led Berzelius and Mitscherlich to define the concept of decomposition of species by contact under a catalytic force . Since then much work has been done in order to understand the behavior of these small transition metal clusters which are able to promote some chemical reactions. In fact, catalysis has become a field of enormous economical interest. It spans a wide variety of areas from oil reforming to the preparation of synthetic fibers or fertilizers. Theoretical research as well as chemical engineering are therefore deeply involved and many current studies deal with the knowledge of such materials. 

Before we begin a detailed discussion of particular enzymes, it is useful to outline the catalytic strategies that we will consider. It is hoped that this represents a relatively complete list of the major catalytic forces in enzymes. 

Faraday was the first to carry out experiments to explore why platinum facilitates the oxidation reactions of different molecules. He found that ethylene adsorption deactivates the platinum surface temporarily while the adsorption of sulfur deactivates platinum permanently. He measured the rate of hydrogen oxidation, suggested a mechanism, and observed its deactivation and regeneration. Thus, Faraday was the first scientist who studied catalytic reactions. In 1836 Berzelius (1, 2] defined the phenomenon and called it catalysis and suggested the existence of a catalytic force" associated with the action of catalysts. 

The catalytic force seems to lie in the fact that certain bodies through their mere presence bring to life relationships that would otherwise only slumber at these temperatures... We have ground to believe that in living plants and animals thousands of catalytic processes take place between the fluids and tissues. ... 

Today, someone might possibly write cin annual review of the coordination chemistry of chromium. But, Baron Jacob Berzelius, the Mr. Chemistry of his day, wrote an annual review of chemistry every year for twenty-eight years. In 1835, he surveyed Kirchoff s work on acid hydrolysis, the catalytic oxidations on platinum and Thenard s work on the decomposition of H2 O2. He discerned a phenomenon common to the three areas, and he invented catalysis and catalyst. Unfortunately, he coined cinother term, catalytic force (6). 

Catalytic force actually mecins that substances are able to awaken affinities which are asleep at this temperature by their mere presence and not by their own affinity." (Emphasis added). 

During the rest of the century, much fruitless effort was devoted to trying to develop explanations for catalytic force. It was this that gave catalysis something of a bad reputation and led to Ostwald s unfriendly remark. However, all through the century there were those who advcinced chemical theories of catalysis. For example, de la Rive (7) in 1838 proposed that platinum catalyzed the oxidation of hydrogen by a cycle of alternate oxidations of platinum followed by reduction of the surface oxide. He said ... 

Ce n est pas necessaire de recourir a une force mysterieuse telle que celle que Berzelius a admise sous le nom de force catalytique. [It is unnecessary to resort to a mysterious force like that which Berzelius has proposed under the name, catalytic force]. ... 

By 1934, the only remaining trace of catalytic force lay in the low temperature catalysis of the interconversion of the newly discovered ortho- and parahydrogen by paramagnetic surface sites. 

Early in the 19th century Berzelius began to recognize a common feature within a number of isolated observations, such as the behaviour of hydrolytic enzyme concentrates in vitro and the effects of acids, platinum metal and other materials on simple chemical reactions. In 1835, he introduced the terms catalytic force and catalysis to describe the property by which some materials, soluble or insoluble, could effect or accelerate a reaction, to which the catalytic material itself remained indifferent . 

Amygdalin was the first example of a glycoside. Wohler and Liebig recognised that the action of the ferment, which they called emulsitty was similar to that of yeast on sugar, which Berzelius has attributed to a peculiar, catalytic, force. ... 

Kekule points out that mass action and catalytic force have an influence on reactions. Generally, the force which brings about the association (Aneinander-lagerung) of the molecules also causes their decomposition (catalysis), but there are cases where the latter does not occur under suitable conditions, and the intermediate product may be isolated. 

In the last edition of his text-book Berzelius gave a short account of the action of this mysterious and occult force, which acts principally on the polarity of the atoms, which is augmented, diminished, or changed by it. In other words, the catalytic force is manifested by the excitation of electrical relations which up to the present have escaped our researches . 

E. C. Jungfleisch suggested that the action of manganese dioxide is chemical potassium permanganate is alternately formed and decomposed. E. J. Mills, G. Donald, and S. J. Stevenson thought there was nothing abnormal in the reaction and it was unnecessary to invoke a special catalytic force . F. Bellamy proposed the reactions ... 

All of this research was reviewed by Berzelius in 1836, who postulated that these experiments demonstrated the Catalytic Force of Bodies and decomposition which it produces. Catalysis The agents of these decompositions he... 

Ostwald merged the two approaches there is not a direct physical catalytic force or action nor a direct modification of the chemical bonds but the thermodynamic of the whole system is changed with new ways of lower free energy in the chemical transformation (Ostwald, 1902). Substantially the actual conception of the phenomena. 

When the concept of catalysis was first formulated, the idea that the catalytic reaction is actually a catalytic cycle was not at aU obvious. In 1836 Berzelius deflned catalytic force as the process responsible for catalysis in which the decomposition of bodies was caused by the action of another simple or compound body. Faraday later showed that a catalytically reactive surface was chemically altered by contact with reacting gases. It was not, however, until after chemical thermodynamics had been developed that a more scientific understanding of catalysis was formulated. In 1896 Van t Hoff demonstrated that the rate of a catalytic reaction depended up)on the amount of catalyst. Soon after Ostwald defined a catalyst to be a substance that changes the velocity of a reaction without itself being altered in the process. A catalyst, however, must operate within the thermodynamic limits of the reacting system PI. 

I shall, therefore. .. call it that body s catalytic force, the decomposition of other bodies by this force catalysis, just as we signify by the word analysis the separation of the constituents of bodies by the usual chemical affinities.]... 

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