Henri Louis Le Chatelier
Encyclopedia
Henri Louis Le Châtelier (8 October 1850 - 17 September 1936) was an influential French
chemist
of the late 19th and early 20th centuries. He is most famous for devising Le Châtelier's principle
, used by chemists to predict the effect a changing condition has on a system in chemical equilibrium
. His disciples now reside in the Humboldt State University Chemistry Department in Arcata, CA.
industry, the introduction of the Martin-Siemens processes into the iron and steel industries, and the rise of railway transportation. Le Châtelier’s father profoundly influenced his son's future.
Henri Louis had one sister (Marie) and four brothers (Louis (1853-1928), Alfred (1855-1929), George (1857-1935), and André (1861-1929)). His mother raised the children by regimen, described by Henri Louis: "I was accustomed to a very strict discipline: it was necessary to wake up on time, to prepare for your duties and lessons, to eat everything on your plate, etc. All my life I maintained respect for order and law. Order is one of the most perfect forms of civilization." (L. Guillet, REVUE DE METALLURGIE, Numéro Spécial, janvier 1937).
As a child, Le Châtelier attended the Collège Rollin
in Paris. At the age of 19, after only one year of instruction in specialized engineering, he followed in his father's footsteps by enrolling in the École polytechnique
on 25 October 1869. Like all the pupils of la polytechnique, in September 1870, Le Châtelier was named second lieutenant and later took part in the Siege of Paris
. After brilliant successes in his technical schooling, he entered the École des Mines in Paris in 1871.
Le Châtelier married Geneviève Nicolas, a friend of the family and sister of four fellow students of la polytechnique. They had seven children, four girls and three boys, five of whom entered scientific fields; two were lost preceding Le Châtelier's death.
At the Collège de France, Le Châtelier succeeded Schützenberger
as chair of inorganic chemistry. Later he taught at the Sorbonne
university, where he replaced Henri Moissan
.
At the Collège de France, Le Châtelier taught:
After four unsuccessful campaigns (1884, 1897, 1898 and 1900), Le Châtelier was elected to the Académie des sciences (Academy of Science) in 1907. He was also elected to the Royal Swedish Academy of Sciences
in 1907.
and on varying solubility of salts in an ideal solution. He published no fewer than thirty papers on these topics between 1884 and 1914. His results on chemical equilibrium were presented in 1885 at the Académie des sciences
in Paris.
Le Châtelier also carried out extensive research on metallurgy and was one of the founders of the technical newspaper "La revue de métallurgie."
Part of Le Châtelier's work was devoted to industry. For example, he was a consulting engineer for a cement company, the Société des chaux et ciments Pavin de Lafarge, today known as Lafarge
Cement. His 1887 doctoral thesis was dedicated to the subject of mortars: Recherches expérimentales sur la constitution des mortiers hydrauliques (Experimental Research on the Composition of Hydraulic Mortars).
Le Chatelier in 1901 attempted the direct combination of the two gases at a pressure of 200 atm and 600⁰C in presence of metallic iron . The mixture of gases was forced by an air compressor into a steel Berthelot bomb, where they and the reduced iron catalyst were heated by a platinum spiral[from 4. "Henri Le Chatelier: His Publications," Ceram. Abs., 16, (Oct., 1937)]. A terrific explosion occurred which nearly killed an assistant. Sometime later Le Chatelier found that the explosion was due to the presence of air in the apparatus used. And’ thus it was left for Haber to succeed where a number of noted French chemists, including Thenard, Sainte Claire Deville and even Berthelot had failed. In less than five years later, Haber and Claude were successful in producing ammonia on a commercial scale, acknowledging that the account of Le Chatelier's failed attempt had accelerated their research. Near the end of his life, Le Chatelier wrote, "I let the discovery of the ammonia synthesis slip through my hands. It was the greatest blunder of my scientific career” [from the last book by Henry Le Chatelier “De la Methode dans les Sciences Expkimentales," published in 1936, pp. 73-76 (http://pubs.acs.org/doi/pdfplus/10.1021/ed015p289.3)]. (Edited by Aniket S Waval.- Institute of Chemical Technology, Mumbai, India.)
Put another way,
If a chemical system at equilibrium experiences a change in concentration, temperature or total pressure, the equilibrium will shift in order to minimize that change.
This qualitative law enables one to envision the displacement of equilibrium of a chemical reaction.
For example:
A change in concentration of a reaction in equilibrium for the following equation:
N2(g) + 3H2(g) ⇌ 2NH3(g)
If one increases the pressure of the reactants (Nitrogen, N2 and Hydrogen, H2) the reaction will tend to move towards the products to decrease the pressure of the reaction.
Another example:
In the Contact Process
for the production of sulphuric acid, the second stage is a reversible reaction:
2SO2(g) + O2(g) ⇌ 2SO3(g)
The forward reaction is exothermic and the reverse reaction is endothermic. If the temperature were increased, the larger amount of thermal energy in the system would favor the endothermic reverse reaction, as this would absorb the increased energy; in other words the equilibrium would shift to the reactants in order to remove the stress of added heat. For similar reasons, lower temperatures would favor the exothermic forward reaction, and produce more products.
. In 1928, he published a book on Taylorism.
Le Châtelier was politically conservative. In 1934, he published an opinion on the French forty-hour work week law in the Brussels publication Revue économique internationale. However, in spite of certain anti-parliamentarian convictions, he kept away from any extremist or radical movements.
in 1887, became "officier" (officer) in 1908, "commandeur" (Knight Commander) in 1919, and was finally awarded the title of "grand officier" (Knight Grand Officer) in May of 1927.
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
chemist
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...
of the late 19th and early 20th centuries. He is most famous for devising Le Châtelier's principle
Le Châtelier's principle
In chemistry, Le Chatelier's principle, also called the Chatelier's principle, can be used to predict the effect of a change in conditions on a chemical equilibrium. The principle is named after Henry Louis Le Chatelier and sometimes Karl Ferdinand Braun who discovered it independently...
, used by chemists to predict the effect a changing condition has on a system in chemical equilibrium
Chemical equilibrium
In a chemical reaction, chemical equilibrium is the state in which the concentrations of the reactants and products have not yet changed with time. It occurs only in reversible reactions, and not in irreversible reactions. Usually, this state results when the forward reaction proceeds at the same...
. His disciples now reside in the Humboldt State University Chemistry Department in Arcata, CA.
Early life
Le Châtelier was born on 8 October 1850 in Paris and was the son of French materials engineer Louis Le Châtelier and Louise Durand. His father was an influential figure who played important roles in the birth of the French aluminiumAluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
industry, the introduction of the Martin-Siemens processes into the iron and steel industries, and the rise of railway transportation. Le Châtelier’s father profoundly influenced his son's future.
Henri Louis had one sister (Marie) and four brothers (Louis (1853-1928), Alfred (1855-1929), George (1857-1935), and André (1861-1929)). His mother raised the children by regimen, described by Henri Louis: "I was accustomed to a very strict discipline: it was necessary to wake up on time, to prepare for your duties and lessons, to eat everything on your plate, etc. All my life I maintained respect for order and law. Order is one of the most perfect forms of civilization." (L. Guillet, REVUE DE METALLURGIE, Numéro Spécial, janvier 1937).
As a child, Le Châtelier attended the Collège Rollin
Collège Rollin
The collège-lycée Jacques-Decour is a school in Paris on the avenue Trudaine.-History:The school was founded as the private collège Sainte-Barbe in 1821, renamed the private collège Rollin in 1830...
in Paris. At the age of 19, after only one year of instruction in specialized engineering, he followed in his father's footsteps by enrolling in the École polytechnique
École Polytechnique
The École Polytechnique is a state-run institution of higher education and research in Palaiseau, Essonne, France, near Paris. Polytechnique is renowned for its four year undergraduate/graduate Master's program...
on 25 October 1869. Like all the pupils of la polytechnique, in September 1870, Le Châtelier was named second lieutenant and later took part in the Siege of Paris
Siege of Paris
The Siege of Paris, lasting from September 19, 1870 – January 28, 1871, and the consequent capture of the city by Prussian forces led to French defeat in the Franco-Prussian War and the establishment of the German Empire as well as the Paris Commune....
. After brilliant successes in his technical schooling, he entered the École des Mines in Paris in 1871.
Le Châtelier married Geneviève Nicolas, a friend of the family and sister of four fellow students of la polytechnique. They had seven children, four girls and three boys, five of whom entered scientific fields; two were lost preceding Le Châtelier's death.
Career
Despite training as an engineer, and even with his interests in industrial problems, Le Châtelier chose to teach chemistry rather than pursue a career in industry. In 1887, he was appointed head of the general chemistry to the preparatory course of the École des Mines in Paris. He tried unsuccessfully to get a position teaching chemistry at the École polytechnique in 1884 and again in 1897.At the Collège de France, Le Châtelier succeeded Schützenberger
Paul Schützenberger
Paul Schützenberger , French chemist, was born at Strasbourg, where his father Georges Frédéric Schützenberger was professor of law, and his uncle Charles Schützenberger professor of chemical medicine....
as chair of inorganic chemistry. Later he taught at the Sorbonne
University of Paris
The University of Paris was a university located in Paris, France and one of the earliest to be established in Europe. It was founded in the mid 12th century, and officially recognized as a university probably between 1160 and 1250...
university, where he replaced Henri Moissan
Henri Moissan
Ferdinand Frederick Henri Moissan was a French chemist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds.-Biography:...
.
At the Collège de France, Le Châtelier taught:
- Phenomena of combustion (1898)
- Theory of the balances chemical, high temperature measurements and phenomena of dissociation (1898-1899)
- Properties of metal alloys (1899-1900)
- Iron alloys (1900-1901)
- General methods of analytical chemistry (1901-1902)
- General laws of analytical chemistry (1901-1902)
- General laws of chemical mechanics (1903)
- Silica and its compounds (1905-1906)
- Some practical applications of the fundamental principles of chemistry (1906-1907)
- Properties of metals and some alloys (1907)
After four unsuccessful campaigns (1884, 1897, 1898 and 1900), Le Châtelier was elected to the Académie des sciences (Academy of Science) in 1907. He was also elected to the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
in 1907.
Scientific work
In chemistry, Le Châtelier is best known for his work on his principle of chemical equilibrium, Le Châtelier's principleLe Châtelier's principle
In chemistry, Le Chatelier's principle, also called the Chatelier's principle, can be used to predict the effect of a change in conditions on a chemical equilibrium. The principle is named after Henry Louis Le Chatelier and sometimes Karl Ferdinand Braun who discovered it independently...
and on varying solubility of salts in an ideal solution. He published no fewer than thirty papers on these topics between 1884 and 1914. His results on chemical equilibrium were presented in 1885 at the Académie des sciences
French Academy of Sciences
The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research...
in Paris.
Le Châtelier also carried out extensive research on metallurgy and was one of the founders of the technical newspaper "La revue de métallurgie."
Part of Le Châtelier's work was devoted to industry. For example, he was a consulting engineer for a cement company, the Société des chaux et ciments Pavin de Lafarge, today known as Lafarge
Lafarge
Lafarge is a French industrial company specialising in four major products: cement, construction aggregates, concrete and gypsum wallboard. In 2010 the company was the world's second-largest cement manufacturer by mass shipped behind Holcim.-History:...
Cement. His 1887 doctoral thesis was dedicated to the subject of mortars: Recherches expérimentales sur la constitution des mortiers hydrauliques (Experimental Research on the Composition of Hydraulic Mortars).
Le Chatelier in 1901 attempted the direct combination of the two gases at a pressure of 200 atm and 600⁰C in presence of metallic iron . The mixture of gases was forced by an air compressor into a steel Berthelot bomb, where they and the reduced iron catalyst were heated by a platinum spiral[from 4. "Henri Le Chatelier: His Publications," Ceram. Abs., 16, (Oct., 1937)]. A terrific explosion occurred which nearly killed an assistant. Sometime later Le Chatelier found that the explosion was due to the presence of air in the apparatus used. And’ thus it was left for Haber to succeed where a number of noted French chemists, including Thenard, Sainte Claire Deville and even Berthelot had failed. In less than five years later, Haber and Claude were successful in producing ammonia on a commercial scale, acknowledging that the account of Le Chatelier's failed attempt had accelerated their research. Near the end of his life, Le Chatelier wrote, "I let the discovery of the ammonia synthesis slip through my hands. It was the greatest blunder of my scientific career” [from the last book by Henry Le Chatelier “De la Methode dans les Sciences Expkimentales," published in 1936, pp. 73-76 (http://pubs.acs.org/doi/pdfplus/10.1021/ed015p289.3)]. (Edited by Aniket S Waval.- Institute of Chemical Technology, Mumbai, India.)
Le Châtelier's principle
Le Châtelier's Principle states that a system always acts to oppose changes in chemical equilibrium; to restore equilibrium, the system will favor a chemical pathway to reduce or eliminate the disturbance so as to restabilize at thermodynamic equilibrium.Put another way,
If a chemical system at equilibrium experiences a change in concentration, temperature or total pressure, the equilibrium will shift in order to minimize that change.
This qualitative law enables one to envision the displacement of equilibrium of a chemical reaction.
For example:
A change in concentration of a reaction in equilibrium for the following equation:
N2(g) + 3H2(g) ⇌ 2NH3(g)
If one increases the pressure of the reactants (Nitrogen, N2 and Hydrogen, H2) the reaction will tend to move towards the products to decrease the pressure of the reaction.
Another example:
In the Contact Process
Contact process
The contact process is the current method of producing sulphuric acid in the high concentrations needed for industrial processes. Platinum was formerly employed as a catalyst for the reaction, but as it is susceptible to poisoning by arsenic impurities in the sulfur feedstock, vanadium oxide is...
for the production of sulphuric acid, the second stage is a reversible reaction:
2SO2(g) + O2(g) ⇌ 2SO3(g)
The forward reaction is exothermic and the reverse reaction is endothermic. If the temperature were increased, the larger amount of thermal energy in the system would favor the endothermic reverse reaction, as this would absorb the increased energy; in other words the equilibrium would shift to the reactants in order to remove the stress of added heat. For similar reasons, lower temperatures would favor the exothermic forward reaction, and produce more products.
His time and politics
It was typical for scientists and engineers of the time to have a very scientific vision of industry. In the first issue of La revue de métallurgie, Le Châtelier published an article describing his convictions on the subject (H. Chatelier, "Role of Science in Industry" in La revue de métallurgie, n°1, 1904 page 1 to 10), discussing the scientific management theory of Frederick Winslow TaylorFrederick Winslow Taylor
Frederick Winslow Taylor was an American mechanical engineer who sought to improve industrial efficiency. He is regarded as the father of scientific management and was one of the first management consultants...
. In 1928, he published a book on Taylorism.
Le Châtelier was politically conservative. In 1934, he published an opinion on the French forty-hour work week law in the Brussels publication Revue économique internationale. However, in spite of certain anti-parliamentarian convictions, he kept away from any extremist or radical movements.
Decorations
Le Châtelier was named "chevalier" (knight) of the Légion d'honneurLégion d'honneur
The Legion of Honour, or in full the National Order of the Legion of Honour is a French order established by Napoleon Bonaparte, First Consul of the Consulat which succeeded to the First Republic, on 19 May 1802...
in 1887, became "officier" (officer) in 1908, "commandeur" (Knight Commander) in 1919, and was finally awarded the title of "grand officier" (Knight Grand Officer) in May of 1927.
Works
- Cours de chimie industrielle (1896; second edition, 1902)
- High Temperature Measurements, translated by G. K. BurgessGeorge Kimball BurgessGeorge Kimball Burgess was an American physicist, considered one of the most notable scientists of his era. He authored and translated numerous studies, was a leading member and president of many scientific societies and, for the last nine years of his life, served as director of the National...
(1901; second edition, 1902) - Recherches expérimentales sur la constitution des mortiers hydrauliques (1904; English translation, 1905)
- Leçons sur le carbone (1908)
- Introduction à l'étude de la métallurge (1912)
- La silice et les silicates (1914)
External links
- Henry LE CHATELIER (1850-1936) Sa vie, son œuvre. Publié dans REVUE DE METALLURGIE, Numéro Spécial, janvier 1937. (In French) http://www.annales.org/archives/x/lc.html