Louis Jacques Thénard (4 May 177721 June 1857) was a French

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

Life

He was born in a farm cottage near

Nogent-sur-Seine Nogent-sur-Seine () is a commune in the Aube department in north-central France. The headquarters of The Soufflet Group is located here, as is the Musée Camille Claudel. The large Nogent Nuclear Power Plant is located here. Population ...

in the Champagne district the son of a farm worker. In the post-Revolution French educational system , most boys received scholarships for education up to age 14, and this allowed him to be educated at the academy at

Sens Sens () is a Communes of France, commune in the Yonne Departments of France, department in Bourgogne-Franche-Comté in north-central France, 120 km from Paris. Sens is a Subprefectures in France, sub-prefecture and the second city of the d ...

. He then went at the age of sixteen to study

pharmacy Pharmacy is the science and practice of discovering, producing, preparing, dispensing, reviewing and monitoring medications, aiming to ensure the safe, effective, and affordable use of medicines. It is a miscellaneous science as it links heal ...

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

. There he attended the lectures of

Antoine François Fourcroy Antoine is a French given name (from the Latin ''Antonius'' meaning 'highly praise-worthy') that is a variant of Danton, Titouan, D'Anton and Antonin. The name is used in France, Switzerland, Belgium, Canada, West Greenland, Haiti, French Guiana ...

and

Louis Nicolas Vauquelin Prof. Louis Nicolas Vauquelin Royal Society of London, FRS(For) HFRSE (16 May 1763 – 14 November 1829) was a French pharmacist and chemist. He was the discoverer of both chromium and beryllium. Early life Vauquelin was born at Saint-André-d'H ...

. He was allowed into Vauquelin's laboratory even though he was unable to pay the monthly fee of 20 francs, due to the requests of Vauquelin's sisters. But his progress was so rapid that in two or three years he was able to take his master's place at the lecture-table, and Fourcroy and Vauquelin were so satisfied with his performance that they procured for him a school appointment in 1797 as teacher of chemistry, and in 1798 one as at the

École Polytechnique École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine flowing in région Île-de-France * École, Savoi ...

Career

In 1804 Vauquelin resigned his professorship at the

Collège de France The Collège de France (), formerly known as the ''Collège Royal'' or as the ''Collège impérial'' founded in 1530 by François I, is a higher education and research establishment (''grand établissement'') in France. It is located in Paris ne ...

and successfully used his influence to obtain the appointment for Thénard, who six years later, after Fourcroy's death, was further elected to the chairs of chemistry at the

and the Faculté des Sciences. He also succeeded Fourcroy as member of the Academy. In 1821, he was elected a foreign member of the

Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special ...

. In 1825 he received the title of baron from

Charles X Charles X (born Charles Philippe, Count of Artois; 9 October 1757 – 6 November 1836) was King of France from 16 September 1824 until 2 August 1830. An uncle of the uncrowned Louis XVII and younger brother to reigning kings Louis XVI and Loui ...

, and in 1832

Louis Philippe Louis Philippe (6 October 1773 – 26 August 1850) was King of the French from 1830 to 1848, and the penultimate monarch of France. As Louis Philippe, Duke of Chartres, he distinguished himself commanding troops during the Revolutionary War ...

made him a peer of France. From 1827 to 1830 he represented the ''

département In the administrative divisions of France, the department (french: département, ) is one of the three levels of government under the national level ("territorial collectivity, territorial collectivities"), between the regions of France, admin ...

'' of

Yonne Yonne () is a department in the Bourgogne-Franche-Comté region in France. It is named after the river Yonne, which flows through it, in the country's north-central part. One of Bourgogne-Franche-Comté's eight constituent departments, it is lo ...

in the chamber of deputies, and as vice-president of the , he exercised a great influence on scientific education in France. He died in Paris on 21 June 1857. A statue was erected to his memory at Sens in 1861, and in 1865 the name of his native village was changed to La Louptière-Thénard. Above all things Thénard was a teacher; as he himself said, the professor, the assistants, the laboratory — everything must be sacrificed to the students. Like most great teachers he published a textbook, and his (4 vols., Paris, 1813–16), which served as a standard for a quarter of a century, perhaps did even more for the advance of chemistry than his numerous original discoveries.

Research

Soon after his appointment as at the École Polytechnique he began a lifelong friendship with

Joseph Louis Gay-Lussac Joseph Louis Gay-Lussac (, , ; 6 December 1778 – 9 May 1850) was a French chemist and physicist. He is known mostly for his discovery that water is made of two parts hydrogen and one part oxygen (with Alexander von Humboldt), for two laws ...

, and the two carried out many research projects together. Careful analysis led him to dispute some of

Claude Louis Berthollet Claude Louis Berthollet (, 9 December 1748 – 6 November 1822) was a Savoyard-French chemist who became vice president of the French Senate in 1804. He is known for his scientific contributions to theory of chemical equilibria via the mecha ...

's theoretical views regarding the composition of the metallic

oxide An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the E ...

s, and he also showed Berthollet's "zoonic acid" to be impure

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

(1802). In response, Berthollet invited him to become a member of the

Society of Arcueil The Society of Arcueil was a circle of French scientists who met regularly on summer weekends between 1806 and 1822 at the country houses of Claude Louis Berthollet and Pierre Simon Laplace at Arcueil, then a village 3 miles south of Paris. Members ...

. In 1806 he analysed the chemical composition of the

Alais meteorite Alais or Allais is the first carbonaceous chondrite meteorite identified. It fell near Alès in 1806 in multiple fragments which together weighed , although only remains. The meteorite contains a number of elements in similar proportions to the ...

, which fell in

Alès Alès (; oc, Alès) is a Communes of France, commune in the Gard Departments of France, department in the Occitania (administrative region), Occitanie regions of France, region in southern France. It is one of the Subprefectures in France, su ...

on 15 March 1806. This was the first

carbonaceous chondrite Carbonaceous chondrites or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites. The C chondrites represent only a small prop ...

to be discovered. Thénard found a high carbon content of 2.5 per cent. His first original paper (1799) was on the compounds of

arsenic Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but ...

and

antimony Antimony is a chemical element with the symbol Sb (from la, stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient time ...

with

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

and

sulphur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...

. In 1807, he began important research into

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...

s. His researches on

sebacic acid Sebacic acid is a naturally occurring dicarboxylic acid with the chemical formula . It is a white flake or powdered solid. ''Sebaceus'' is Latin for tallow candle, ''sebum'' is Latin for tallow, and refers to its use in the manufacture of candles. ...

(1802) and on

bile Bile (from Latin ''bilis''), or gall, is a dark-green-to-yellowish-brown fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is produced continuously by the liver (liver bile ...

(1807) deserve mention as well, as does his discovery of

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

(1818).L. J. Thénard (1818
"Observations sur des nouvelles combinaisons entre l’oxigène et divers acides,"
''Annales de chimie et de physique'', 2nd series, vol. 8, pages 306-312; see especially page 308. In 1799 he developed the pigment known as Thénard's blue in response to a request by

Jean-Antoine-Claude Chaptal Jean-Antoine Chaptal, comte de Chanteloup (5 June 1756 – 30 July 1832) was a French chemist, physician, agronomist, industrialist, statesman, educator and philanthropist. His multifaceted career unfolded during one of the most brilliant peri ...

for a cheap colouring matter. His name is one of the 72 names inscribed on the Eiffel Tower.

Works

* ** **

References

Attribution: * {{DEFAULTSORT:Thenard, Louis Jacques 1777 births 1857 deaths 18th-century French chemists French Roman Catholics Members of the French Academy of Sciences Members of the Royal Swedish Academy of Sciences Foreign Members of the Royal Society 19th-century French chemists