Anry Le Chatelier French physicist and chemist. Date of Birth: 08.10.1850 Country: France

Biography of Henri Le Chatelier

Henri Le Chatelier was a French physicist and chemist. Born into a family of mining engineers, his father instilled in him a love for science from an early age. Le Chatelier studied at the College Rollin in Paris, the Polytechnic School, and the Higher Mining School. He worked in the laboratory of A.E. Sainte-Claire Deville and attended lectures at the College de France. In addition to natural sciences, Le Chatelier was also interested in religion and ancient languages.

After graduating from the Higher Mining School, Le Chatelier worked as a mining engineer in Algeria and Besançon. From 1877 to 1919, he served as a professor at the Paris Higher Mining School, teaching general and technical chemistry. He was also a professor of general chemistry at the College de France (1898-1907) and the University of Paris (1907-1925). In 1907, he was elected a member of the Paris Academy of Sciences.

Most of Le Chatelier's work focused on applied problems. He was one of the first chemists to systematically conduct fundamental research on metallurgical and chemical-technological processes. In 1880, Le Chatelier began studying the burning and hardening of cement. At that time, existing research did not provide an explanation for these complex processes. Based on his studies, he developed the theory of cement hardening, also known as the "crystallization" theory.

In 1881, together with M. Berthelot and F. Mallard, Le Chatelier began researching processes of ignition, combustion, and explosion. These studies led him to create an original method for determining the heat capacities of gases at high temperatures. While studying the processes occurring in blast furnaces and the need to measure high temperatures, Le Chatelier developed the pyrometer in 1886 - an optical instrument for measuring the temperature of heated bodies based on their color. He also improved the methodology for studying metals and alloys and created the metallographic microscope in 1897, which allowed for the examination of the structure of opaque objects.

In 1884, Le Chatelier formulated the principle of dynamic equilibrium, now bearing his name (independently of Le Chatelier, the principle was also formulated by C.F. Braun in 1887). According to this principle, a system in a state of stable chemical equilibrium, when subjected to external influences (such as temperature, pressure, concentration of reacting substances, etc.), seeks to return to equilibrium by compensating for the applied effect. The Le Chatelier-Braun principle is used to model various technological processes.

In 1894, Le Chatelier derived an equation that established the relationship between solubility, the temperature of the process, and the heat of fusion of a substance. Independently of F. Haber in 1901, Le Chatelier found the conditions for synthesizing ammonia. With his active participation, physical chemistry and chemical technology became independent and rapidly developing fields of science.

Le Chatelier received numerous awards throughout his career. In 1886, he became a Knight of the Legion of Honor, and in 1916, he was awarded the Davy Medal by the Royal Society of London.