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Jean Baptiste André Dumas (French pronunciation: [ʒɑ̃ batist ɑ̃dʁe dyma]; 14 July 1800 – 10 April 1884) was a French chemist, best known for his works on organic analysis and synthesis, as well as the determination of atomic weights (relative atomic masses) and molecular weights by measuring vapor densities.
The Dumas method of molecular weight determination was historically a procedure used to determine the molecular weight of an unknown volatile substance. [ 1 ] [ 2 ] The method was designed by the French chemist Jean Baptiste André Dumas , after whom the procedure is now named.
The Dumas technique has been automated and instrumentalized, so that it is capable of rapidly measuring the crude protein concentration of food samples. This automatic Dumas technique has replaced the Kjeldahl method as the standard method of analysis for nutritional labelling of protein content of foods (except in high fat content foods where ...
Journal de la Montagne; Journal de l'opposition : Pierre-François Réal; Journal de Paris : Corancez, Antoine Cadet de Vaux, Dussieux, N. Xhrouet; Journal de Paris : Michel Louis Étienne Regnault de Saint-Jean d'Angely; Journal de Perlet : Charles Frédéric Perlet; Journal des amis de la Constitution : Pierre Choderlos de Laclos
Jean-Baptiste Dumas used the terms "physical atoms" and "chemical atoms"; a "physical atom" was a particle that cannot be divided by physical means such as temperature and pressure, and a "chemical atom" was a particle that could not be divided by chemical reactions. [26]
He later switched to chemistry and worked at the École Polytechnique in Paris under the direction of Jean-Baptiste Dumas. Stas and Dumas established the atomic weight of carbon by weighing a sample of the pure material, burning it in pure oxygen , and then weighing the carbon dioxide produced.
It is not always the case that the structure of a molecule is easy to relate to its function. What makes the structure of DNA so obviously related to its function was described modestly at the end of the article: "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material".
He collaborated with Jean-Baptiste Dumas, and together they discovered the methyl radical during experiments on wood spirit . The terminology "methyl alcohol" was created by both chemists from "wood wine". They also prepared the gaseous dimethyl ether, and many esters.