Jean-Baptiste Dumas
Encyclopedia
Jean Baptiste André Dumas (14 July 1800 – 10 April 1884) was a French
French people
The French are a nation that share a common French culture and speak the French language as a mother tongue. Historically, the French population are descended from peoples of Celtic, Latin and Germanic origin, and are today a mixture of several ethnic groups...

 chemist
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...

, best known for his works on organic analysis and synthesis, as well as the determination of atomic weight
Atomic weight
Atomic weight is a dimensionless physical quantity, the ratio of the average mass of atoms of an element to 1/12 of the mass of an atom of carbon-12...

s (relative atomic masses) and molecular weights by measuring vapor
Vapor
A vapor or vapour is a substance in the gas phase at a temperature lower than its critical point....

 densities. He also developed a method for the analysis of nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...

 in compounds.

Life

Dumas was born in Alès
Alès
Alès is a commune in the Gard department in the Languedoc-Roussillon region in southern France. It is one of the sub-prefectures of the department. It was formerly known as Alais.-Geography:...

 (Gard
Gard
Gard is a département located in southern France in the Languedoc-Roussillon region.The department is named after the River Gard, although the formerly Occitan name of the River Gard, Gardon, has been replacing the traditional French name in recent decades, even among French speakers.- History...

), and became an apprentice to an apothecary
Apothecary
Apothecary is a historical name for a medical professional who formulates and dispenses materia medica to physicians, surgeons and patients — a role now served by a pharmacist and some caregivers....

 in his native town. In 1816, he moved to Geneva
Geneva
Geneva In the national languages of Switzerland the city is known as Genf , Ginevra and Genevra is the second-most-populous city in Switzerland and is the most populous city of Romandie, the French-speaking part of Switzerland...

, where he attended lectures by M. A. Pictet in physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

, C. G. de la Rive in chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

, and A. P. de Candolle
A. P. de Candolle
Augustin Pyramus de Candolle also spelled Augustin Pyrame de Candolle was a Swiss botanist. René Louiche Desfontaines launched Candolle's botanical career by recommending him at an herbarium...

 in botany
Botany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...

, and before he had reached his majority, he was engaged with Pierre Prévost
Pierre Prévost
Pierre Prévost was a Swiss philosopher and physicist. In he showed that all bodies radiate heat, no matter how hot or cold they are.-Life:...

 in original work on problems of physiological chemistry
Physiological chemistry
Physiological chemistry is the chemistry of the organs and tissues of the body and of the various physiological processes incident to life. Physiological chemistry is essentially the precursor to modern biochemistry. In the nineteenth century, physiological chemistry dealt primarily with...

 and even of embryology
Embryology
Embryology is a science which is about the development of an embryo from the fertilization of the ovum to the fetus stage...

. In 1822, he moved to Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

, acting on the advice of Alexander von Humboldt
Alexander von Humboldt
Friedrich Wilhelm Heinrich Alexander Freiherr von Humboldt was a German naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt...

, where he became professor of chemistry, initially at the Lyceum
Lyceum
The lyceum is a category of educational institution defined within the education system of many countries, mainly in Europe. The definition varies between countries; usually it is a type of secondary school.-History:...

, later (1835) at the École polytechnique
École Polytechnique
The École Polytechnique is a state-run institution of higher education and research in Palaiseau, Essonne, France, near Paris. Polytechnique is renowned for its four year undergraduate/graduate Master's program...

. He was one of the founders of the École centrale des arts et manufactures (later named École centrale Paris
École Centrale Paris
École Centrale Paris is a French university-level institution in the field of engineering. It is also known by its original name École centrale des arts et manufactures, or ECP. Founded in 1829, it is one of the oldest and most prestigious engineering schools in France and has the special status...

) in 1829.

In 1832 Dumas became a member of the French Academy of Sciences
French Academy of Sciences
The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research...

. From 1868 until his death in 1884 he would serve the academy as the permanent secretary for its department of Physical Sciences. In 1838, Dumas was elected a foreign member of the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...

.

After 1848, he exchanged much of his scientific work for ministerial posts under Napoléon III
Napoleon III of France
Louis-Napoléon Bonaparte was the President of the French Second Republic and as Napoleon III, the ruler of the Second French Empire. He was the nephew and heir of Napoleon I, christened as Charles Louis Napoléon Bonaparte...

. He became a member of the National Legislative Assembly. He acted as minister of agriculture and commerce for a few months in 1850-1851, and subsequently became a senator, president of the municipal council of Paris, and master of the French mint, but his official career came to a sudden end with the fall of the Second Empire
Second French Empire
The Second French Empire or French Empire was the Imperial Bonapartist regime of Napoleon III from 1852 to 1870, between the Second Republic and the Third Republic, in France.-Rule of Napoleon III:...

.

Dumas was a devout Catholic who would often defend Christian views against critics.

Dumas died at Cannes
Cannes
Cannes is one of the best-known cities of the French Riviera, a busy tourist destination and host of the annual Cannes Film Festival. It is a Commune of France in the Alpes-Maritimes department....

 in 1884, and is buried at the Montparnasse Cemetery
Montparnasse Cemetery
Montparnasse Cemetery is a cemetery in the Montparnasse quarter of Paris, part of the city's 14th arrondissement.-History:Created from three farms in 1824, the cemetery at Montparnasse was originally known as Le Cimetière du Sud. Cemeteries had been banned from Paris since the closure, owing to...

 in Paris, in a large tomb near the back wall. His is one of the 72 names inscribed on the Eiffel tower
The 72 names on the Eiffel Tower
On the Eiffel Tower, seventy-two names of French scientists, engineers and some other notable people are engraved in recognition of their contributions. This is according to the design by Gustave Eiffel. The engravings are found on the sides of the tower under the first balcony...

.

Scientific work

Dumas was one of the first to criticise the electro-chemical doctrines of Jöns Jakob Berzelius
Jöns Jakob Berzelius
Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...

, which at the time his work began were widely accepted as the true theory of the constitution of compound bodies, and opposed a unitary view to the dualistic conception of the Swedish chemist. In a paper on the atomic theory, published in 1826, he anticipated to a remarkable extent some ideas which are frequently supposed to belong to a later period; and the continuation of these studies led him to the ideas about substitution ( metalepsis ) which were developed about 1839 into the theory ( Older Style Theory ) that in organic chemistry
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...

 there are certain types which remain unchanged even when their hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 is replaced by an equivalent quantity of a halide
Halide
A halide is a binary compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative than the halogen, to make a fluoride, chloride, bromide, iodide, or astatide compound. Many salts are halides...

 element. Many of his well-known researches were carried out in support of these views, one of the most important being that on the action of chlorine
Chlorine
Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...

 on acetic acid
Acetic acid
Acetic acid is an organic compound with the chemical formula CH3CO2H . It is a colourless liquid that when undiluted is also called glacial acetic acid. Acetic acid is the main component of vinegar , and has a distinctive sour taste and pungent smell...

 to form trichloroacetic acid
Trichloroacetic acid
Trichloroacetic acid is an analogue of acetic acid in which the three hydrogen atoms of the methyl group have all been replaced by chlorine atoms....

 - a derivative of essentially the same character as the acetic acid itself.

In an 1826 paper, he described his method for ascertaining vapour densities, and the redeterminations which he undertook by its aid of the atomic weight
Atomic weight
Atomic weight is a dimensionless physical quantity, the ratio of the average mass of atoms of an element to 1/12 of the mass of an atom of carbon-12...

s of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

 proved the forerunners of a long series which included some thirty of the elements, the results being mostly published in 1858-1860. He showed "in all elastic fluids observed under the same conditions, the molecules are placed at equal distances".

In 1833, Dumas developed a method for estimating the amount of nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...

 in an organic compound
Organic compound
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

, founding modern analysis methods.

Dumas showed that kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...

s remove urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....

 from the blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

.

Dumas established new values for the atomic mass
Atomic mass
The atomic mass is the mass of a specific isotope, most often expressed in unified atomic mass units. The atomic mass is the total mass of protons, neutrons and electrons in a single atom....

 of thirty elements, setting the value for hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 to 1.

The classification of organic compounds into homologous series was advanced as one consequence of his researches into the acids generated by the oxidation of the alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....

s.

External Links


Further reading

  • Tiffeneau, Marc
    Marc Tiffeneau
    Marc Émile Pierre Adolphe Tiffeneau was a French chemist who discovered the Tiffeneau-Demjanov rearrangement.Tiffeneau received his Ph.D in science in 1907 and his Ph.D in medicine in 1910....

     (1934). Jean-Baptiste Dumas (1800-1884), Paris, Laboratoires G. Beytout.
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