In chemistry, Le Chatelier is best known for his work on his principle of chemical equilibrium,
Le Chatelier's principle, 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 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 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 and
acetylene 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 and together they obtain a perfectly stable flame and the
oxyacetylene 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 to succeed where several noted French chemists, including Thenard, Sainte Claire Deville and even Berthelot had failed. Less than five years later, Haber and
Carl Bosch were successful in producing ammonia on a commercial scale. 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”. His brother
Alfred Le Chatelier, a former soldier, opened the Atelier de Glatigny in the rural area of Glatigny (
Le Chesnay), near Versailles, in 1897. The workshop made
sandstone ceramics, high-quality
porcelain and glassware. In 1901, the critic
Henri Cazalis (alias Jean Lahor), listed the workshop as one of the best producers in France of
Art Nouveau ceramics. Henry Louis 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.
Le Chatelier's principle Le Chatelier'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) + 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 for the production of
sulfuric acid, 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==