Phlogiston theory

the phlogiston theory went through a series of modifications throughout this period. In the old phlogiston theory, phlogiston was believed to be equivalent to minus oxygen in the later theory, it was proposed to be hydrogen (Cavendish, 

Beraut, Dissertation sur la Cause de VAugmentation de Poids, que certaines Matieres acquire rent dans leur Calcination, Bordeaux (1747) [cited in J.R. Partington, A Short History of Chemistry, 3rd ed., p. 149, Dover Publications, New York (1989)]. 

Partington, A Short History of Chemistry, 3rd ed.. Chapter V, Dover Publications, New York 

It should be mentioned that even at its height of popularity, there were chemists who were skeptical of the phlogiston theory. Nicolas Lemery (1645-1715), for instance, did not adopt the theory of phlogiston.  

In spite of the fact that the phlogiston theory made it possible for a large number of facts to be coordinated into a system, it nevertheless retarded the progress of chemistry and prevented a number of the best chemists from seeing the correct explanation of the facts they uncovered. So until it, along with the four-element theory, were comprehensively rejected, modem chemistry remained unfounded for earth, air, water, and fire are not the elements, and substances do not bum because of the presence in them of a common principle of inflammability. 

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Stahl subsequently renamed the terra pingnis phlogiston, the motion of fire (or heat), the essential element of all combnstible materials. Thns the phlogiston theory was born to explain all combnstion and was widely accepted for most of the eighteenth centnry by, among others, such luminaries of chemistry as Joseph Priestley. 

In 1783 Lavoisier annonnced a basic reevalnation of the chemical theory, rejecting the phlogiston theory completely. At the same time, he elevated oxygen to a general explanatory principle (in a manner... 

In the days of alchemy and the phlogiston theory, no system of nomenclature that would be considered logical ia the 1990s was possible. Names were not based on composition, but on historical association, eg, Glauber s salt for sodium sulfate decahydrate and Epsom salt for magnesium sulfate physical characteristics, eg, spirit of wiae for ethanol, oil of vitriol for sulfuric acid, butter of antimony for antimony trichloride, Hver of sulfur for potassium sulfide, and cream of tartar for potassium hydrogen tartrate or physiological behavior, eg, caustic soda for sodium hydroxide. Some of these common or trivial names persist, especially ia the nonchemical Hterature. Such names were a necessity at the time they were iatroduced because the concept of molecular stmcture had not been developed, and even elemental composition was incomplete or iadeterminate for many substances. 

A. L. Lavoisier recognized oxygen as an element, developed the modem theory of combustion, and demolished the phlogiston theory. 

The reasoning here is reminiscent of the negative mass that had to be postulated to support the phlogiston theory. 

These genealogies, of course, take their point of origin not in ordinary people but in heroic figures who fought enemies, even villains, and who won their battles by wit and dexterity. Lavoisier s triumph over the evil forces of Georg Stahl and phlogiston theory is well known, and unlike most heroic scientists, Lavoisier met a martyr s end in the epic events of the French Revolution. This is historical mythology, a crucial constitutive element of the discipline. 3 5... 

See Jean-Baptiste Dumas, who argued that Lavoisier s experiment of 1772 led to the overthrow of the phlogiston theory and founded modem chemistry, in Legons sur la philosophic chimique (Paris Ebrard,... 

The phlogiston theory was mainly due to Georg Ernst Stahl (1660-1734), Becher (1635-1682) had attempted to revive the once universally accepted sulphur-mercury-salt theory of the alchemists in a somewhat modified form, by the assumption that all substances consist of three earths — the... 

In fact, this discovery, and the realisation of its significance by Lavoisier, led to the abandonment of the phlogiston theory and, with his other work, established the basis of modem chemistry. 

Engels compares the overturning of the phlogiston theory with Marx s discovery of surplus value. He writes ... 

Pierre Joseph Macquer (1718—84) was known as a pracdcal chemist (he supervised the royal porcelain factory, for instance). He wrote an influential dictionary (1766 revised in 1778), and he is best known for being a supporter of precisely the phlogiston theory that Lavoisier helped to overturn. 

No one had ever isolated phlogiston, and this hypothetical substance apparently behaved in a contradictory manner. Nevertheless, an incorrect theory was quickly accepted, because what chemistry desperately needed then was a theory that could be used to guide research. The phlogiston theory, as we shall see, performed this function admirably. 

A more nearly correct theory of calcination and combustion had been proposed in the previous century. In 1630 the Frenchman Jean Rey theorized that the weight increase during calcination came about because air was incorporated into the calx. However, by the time the phlogiston theory was proposed, Rey s idea had been forgotten. It... 

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