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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.
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 ...
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.
The year 1873, by many accounts, was a seminal point in the history of the development of the concept of the "molecule". In this year, the renowned Scottish physicist James Clerk Maxwell published his famous thirteen page article 'Molecules' in the September issue of Nature. [15] In the opening section to this article, Maxwell clearly states:
[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."
On the Eiffel Tower, 72 names of French men (scientists, engineers, and mathematicians) are engraved in recognition of their contributions. [1] Gustave Eiffel chose this "invocation of science" because of his concern over the protests against the tower, and chose names of those who had distinguished themselves since 1789. [2]