HOME

TheInfoList



OR:

Henry Louis Le Chatelier (; 8 October 1850 – 17 September 1936) was a French
chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...
of the late 19th and early 20th centuries. He devised
Le Chatelier's principle Le Chatelier's principle (pronounced or ), also called Chatelier's principle (or the Equilibrium Law), is a principle of chemistry used to predict the effect of a change in conditions on chemical equilibria. The principle is named after French ...
, used by chemists and chemical engineers to predict the effect a changing condition has on a system in
chemical equilibrium In a chemical reaction, chemical equilibrium is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the ...
.


Early life

Le Chatelier was born on 8 October 1850 in Paris and was the son of French materials engineer
Louis Le Chatelier Louis Le Chatelier (20 February 1815 – 10 November 1873) was a French chemist and industrialist who developed a method for producing aluminium from bauxite in 1855. His son was chemist Henry Louis Le Chatelier. His name is inscribed on the Eiffe ...
and Louise Durand. His father was an influential figure who played important roles in the birth of the French
aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...
industry, the introduction of the Martin-Siemens processes into the iron and steel industries, and the rise of railway transportation. Le Chatelier's father profoundly influenced his son's future. Henry 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 Henry 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." As a child, Le Chatelier attended the
Collège Rollin In France, secondary education is in two stages: * ''Collèges'' () cater for the first four years of secondary education from the ages of 11 to 15. * ''Lycées'' () provide a three-year course of further secondary education for children between ...
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 may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine flowing in région Île-de-France * École, Savoi ...
on 25 October 1869. Like all the pupils of the Polytechnique, in September 1870, Le Chatelier 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 École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine flowing in région Île-de-France * École, S ...
in Paris in 1871. Le Chatelier married Geneviève Nicolas, a friend of the family and sister of four fellow students of the Polytechnique. They had seven children, four girls and three boys, five of whom entered scientific fields; two died preceding Le Chatelier's death.


Career

Despite training as an engineer, and even with his interests in industrial problems, Le Chatelier 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 Chatelier succeeded Schützenberger as chair of inorganic chemistry. Later he taught at the
Sorbonne Sorbonne may refer to: * Sorbonne (building), historic building in Paris, which housed the University of Paris and is now shared among multiple universities. *the University of Paris (c. 1150 – 1970) *one of its components or linked institution, ...
university, where he replaced
Henri Moissan Ferdinand Frédéric Henri Moissan (28 September 1852 – 20 February 1907) was a French chemist and pharmacist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds. Moissan was one of the original mem ...
. At the Collège de France, Le Chatelier taught: :*Phenomena of combustion (1898) :*Theory of chemical equilibria, 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 Chatelier was elected to the Académie des sciences (Academy of Science) in 1907. He was also elected to the
Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) is one of the royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for prom ...
in 1907. In 1924, he became an Honorary Member of the
Polish Chemical Society The Polish Chemical Society ( pl, Polskie Towarzystwo Chemiczne, PTCHEM) is a professional scientific society of Polish chemists. History The society was founded of 118 Charter Members on 29 June 1919 on the initiative of Leon Marchlewski, Sta ...
.


Scientific work

In chemistry, Le Chatelier is best known for his work on his principle of chemical equilibrium,
Le Chatelier's principle Le Chatelier's principle (pronounced or ), also called Chatelier's principle (or the Equilibrium Law), is a principle of chemistry used to predict the effect of a change in conditions on chemical equilibria. The principle is named after French ...
, 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 1884 at the
Académie des sciences The French Academy of Sciences (French: ''Académie des 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. It was at ...
in Paris. Le Chatelier also carried out extensive research on metallurgy and was one of the founders of the technical newspaper ''La revue de métallurgie'' (Metallurgy Review). Part of Le Chatelier'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 La Farge, LaFarge or Lafarge can refer to: People * Antoinette LaFarge (1966–), American artist and writer * Christopher Grant LaFarge (1862–1938), American architect and partner in the firm Heins & LaFarge * Christopher Grant La Farge ( ...
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). On the advice of a paper of Le Chatelier that the combustion of a mixture of
oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements ...
and
acetylene Acetylene ( systematic name: ethyne) is the chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure ...
in equal parts rendered a flame of more than 3000 celsius, in 1899 Charles Picard (1872-1957) started to investigate this phenomenon but failed because of soot deposits. In 1901 the latter consulted with
Edmond Fouché Edmond is a given name related to Edmund. Persons named Edmond include: * Edmond Canaple (1797–1876), French politician * Edmond Chehade (born 1993), Lebanese footballer * Edmond Conn (1914–1998), American farmer, businessman, and politician ...
and together they obtain a perfectly stable flame and the
oxyacetylene Principle of burn cutting Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, ...
industry was born. In 1902 Fouché invented a gas welder tool with French patent number 325,403 and in 1910 Picard developed the needle valve. Le Chatelier in 1901 attempted the direct combination of the two gases nitrogen and hydrogen at a pressure of 200 atm and 600 °C in the presence of metallic iron. An air compressor forced the mixture of gases into a steel Berthelot bomb, where a platinum spiral heated them and the reduced iron catalyst. A terrific explosion occurred which nearly killed an assistant. Le Chatelier found that the explosion was due to the presence of air in the apparatus used. And thus it was left for
Fritz Haber Fritz Haber (; 9 December 186829 January 1934) was a German chemist who received the Nobel Prize in Chemistry in 1918 for his invention of the Haber–Bosch process, a method used in industry to synthesize ammonia from nitrogen gas and hydroge ...
to succeed where several noted French chemists, including Thenard, Sainte Claire Deville and even Berthelot had failed. 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”.


Le Chatelier's principle

Le Chatelier's Principle states that a system always acts to oppose changes in
chemical equilibrium In a chemical reaction, chemical equilibrium is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the ...
; 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 In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture. Several types of mathematical description can be distinguished: '' mass concentration'', '' molar concentration'', ''number concentration'', ...
,
temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied o ...
or total
pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country a ...
, 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) + 3 H2(g) ⇌ 2 NH3(g) If one increases the pressure of the reactants, the reaction will tend to move towards the products to decrease the pressure of the reaction. However consider another example: in the
contact process The contact process is the current method of producing sulfuric acid in the high concentrations needed for industrial processes. Platinum was originally used as the catalyst for this reaction; however, as it is susceptible to reacting with arsenic ...
for the production of
sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular fo ...
, the second stage is a reversible reaction: :2 SO2(g) + O2(g) ⇌ 2 SO3(g) The forward reaction is exothermic and the reverse reaction is endothermic. Viewed by Le Chatelier's principle a 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. This works in this case, since due to loss of entropy the reaction becomes less exothermic as temperature increases; however reactions that become more exothermic as temperature increases would seem to violate this principle.


Politics

It was then typical for scientists and engineers to have a very scientific vision of industry. In the first issue of ''La revue de métallurgie'', Le Chatelier published an article describing his convictions on the subject,H.L. Le Chatelier, "Role of Science in Industry" in ''La revue de métallurgie'', n°1, 1904 page 1 to 10 discussing the
scientific management Scientific management is a theory of management that analyzes and synthesizes workflows. Its main objective is improving economic efficiency, especially labor productivity. It was one of the earliest attempts to apply science to the engine ...
theory of
Frederick Winslow Taylor Frederick Winslow Taylor (March 20, 1856 – March 21, 1915) was an American mechanical engineer. He was widely known for his methods to improve industrial efficiency. He was one of the first management consultants. In 1909, Taylor summed up ...
. In 1928, he published a book on
Taylorism Scientific management is a theory of management that analyzes and synthesizes workflows. Its main objective is improving economic efficiency, especially labor productivity. It was one of the earliest attempts to apply science to the engineeri ...
. Le Chatelier 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. His brother
Alfred Le Chatelier Frédéric Alfred Le Chatelier (23 November 1855 – 9 August 1929) was a French soldier, ceramicist and Islamologist. He spent most of his military career in the French African colonies. After leaving the army he was involved in a project to bu ...
, a former soldier, opened the Atelier de Glatigny in the rural area of Glatigny (
Le Chesnay Le Chesnay () is a former commune in the Yvelines department in the Île-de-France region in north-central France. On 1 January 2019, it was merged into the new commune Le Chesnay-Rocquencourt. It is located in the western suburbs of Paris, fr ...
), near Versailles, in 1897. The workshop made sandstone ceramics, high-quality porcelain and glassware. In 1901, the critic
Henri Cazalis Henri Cazalis (; 9 March 1840, Cormeilles-en-Parisis, Val-d'Oise – 1 July 1909, Geneva) was a French physician who was a symbolist poet and man of letters and wrote under the pseudonyms of Jean Caselli and Jean Lahor. His works include: *''Chan ...
(alias Jean Lahor), listed the workshop as one of the best producers in France of
Art Nouveau Art Nouveau (; ) is an international style of art, architecture, and applied art, especially the decorative arts. The style is known by different names in different languages: in German, in Italian, in Catalan, and also known as the Modern ...
ceramics. Henry Louis Le Chatelier seems to have encouraged Alfred's workshop and assisted with experiments in the composition of porcelain and the reactions of quartz inclusions, and also designed a thermoelectric pyrometer to measure temperature in the kilns.


Works

* ''Cours de chimie industrielle'' (1896; second edition, 1902) * ''High Temperature Measurements'', translated by G. K. Burgess (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 métallurgie'' (1912) * ''La silice et les silicates'' (1914)


Honours and awards

Le Chatelier was named "chevalier" (knight) of the
Légion d'honneur The National Order of the Legion of Honour (french: Ordre national de la Légion d'honneur), formerly the Royal Order of the Legion of Honour ('), is the highest French order of merit, both military and civil. Established in 1802 by Napoleon ...
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 1927. He was admitted to the
Academie des Sciences The French Academy of Sciences (French: ''Académie des 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. It was at the ...
in 1907. He was awarded the
Bessemer Gold Medal The Bessemer Gold Medal is awarded annually by the Institute of Materials, Minerals and Mining (IOM3) "for outstanding services to the steel industry, to the inventor or designer of any significant innovation in the process employed in the manufact ...
of the British
Iron and Steel Institute The Iron and Steel Institute was an English association organized by the iron trade of the north of England. Its object was the discussion of practical and scientific questions connected with the manufacture of iron and steel. History The first mee ...
in 1911, admitted as a
Foreign Member of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathematic ...
in 1913 and awarded their
Davy Medal The Davy Medal is awarded by the Royal Society of London "for an outstandingly important recent discovery in any branch of chemistry". Named after Humphry Davy, the medal is awarded with a monetary gift, initially of £1000 (currently £2000). H ...
in 1916.


References


Sources

*


External links

*"Henry LE CHATELIER (1850–1936) Sa vie, son œuvre." ''Révue de Métallurgie'', special edition, January 1937

{{DEFAULTSORT:Le Chatelier, Henry 1850 births 1936 deaths École Polytechnique alumni Mines ParisTech alumni Corps des mines 19th-century French chemists 20th-century French chemists Members of the French Academy of Sciences Members of the Royal Swedish Academy of Sciences University of Paris alumni Collège de France faculty Scientists from Paris University of Paris faculty French science writers Foreign Members of the Royal Society Grand Officiers of the Légion d'honneur Bessemer Gold Medal French male non-fiction writers Members of the Ligue de la patrie française