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Dumas was born in Alès (), and became an apprentice to an apothecary in his native town. [3] In 1816, he moved to Geneva, where he attended lectures by M. A. Pictet in physics, C. G. de la Rive in chemistry, and A. P. de Candolle in botany, and before he had reached his majority, he was engaged with Pierre Prévost in original work on problems of physiological chemistry and embryology. [4]
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.
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]
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 ...
In 1826, building on the work of Avogadro, the French chemist Jean-Baptiste Dumas states: Gases in similar circumstances are composed of molecules or atoms placed at the same distance, which is the same as saying that they contain the same number in the same volume.
Shunned by Dumas, he eked out a living teaching in the mineral engineering lab - where he taught a young Louis Pasteur how to crystalize tartaric acid. Laurent died in Paris from tuberculosis . Alexander Williamson in England read Laurent's writing, leading to the Williamson Ether Synthesis that confirmed the validity of Laurent's approach.
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.
[3] [5] Continuing Johann Wolfgang Döbereiner's work with triads and Jean-Baptiste Dumas' families of similar elements, he published in 1865 his "Law of Octaves", which stated that "any given element will exhibit analogous behaviour to the eighth element following it in the table."