Henri Victor Regnault (21 July 1810 – 19 January 1878) 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 ...

and

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

best known for his careful measurements of the thermal properties of gases. He was an early

thermodynamicist In thermodynamics, a thermodynamicist is someone who studies thermodynamic processes and phenomena, i.e. the physics that deal with mechanical action and relations of heat. Among the well-known number of famous thermodynamicists, include Sadi Car ...

and was mentor to William Thomson in the late 1840s. He never used his first given name, and was known throughout his lifetime as Victor Regnault.

Biography

Born in

Aix-la-Chapelle Aachen ( ; ; Aachen dialect: ''Oche'' ; French and traditional English: Aix-la-Chapelle; or ''Aquisgranum''; nl, Aken ; Polish: Akwizgran) is, with around 249,000 inhabitants, the 13th-largest city in North Rhine-Westphalia, and the 28th- ...

in 1810 (modern Aachen, Germany and at that time under French rule), he moved to Paris at the age of eight, following the death of his parents. There, he worked for an upholstery firm until he was eighteen. In 1830, he was admitted to 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 ...

, and in 1832 he graduated from the

École des mines 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, S ...

. Working under

Justus von Liebig Justus Freiherr von Liebig (12 May 1803 – 20 April 1873) was a German scientist who made major contributions to agricultural and biological chemistry, and is considered one of the principal founders of organic chemistry. As a professor at th ...

Gießen Giessen, spelled Gießen in German (), is a town in the German state (''Bundesland'') of Hesse, capital of both the district of Giessen and the administrative region of Giessen. The population is approximately 90,000, with roughly 37,000 univers ...

, Regnault distinguished himself in the nascent field of

organic chemistry Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J ...

by synthesizing several

chlorinated In chemistry, halogenation is a chemical reaction that entails the introduction of one or more halogens into a compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers ...

hydrocarbons In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

(e.g.

vinyl chloride Vinyl chloride is an organochloride with the formula H2C=CHCl. It is also called vinyl chloride monomer (VCM) or chloroethene. This colorless compound is an important industrial chemical chiefly used to produce the polymer polyvinyl chloride (PVC ...

polyvinylidene chloride Polyvinylidene chloride, or polyvinylidene dichloride (PVDC), is a homopolymer of vinylidene chloride. History Ralph Wiley accidentally discovered polyvinylidene chloride polymer in 1933. He, then, was a college student who worked part-time at D ...

dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible wit ...

), and he was appointed professor of chemistry at the University of

Lyon Lyon,, ; Occitan: ''Lion'', hist. ''Lionés'' also spelled in English as Lyons, is the third-largest city and second-largest metropolitan area of France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of ...

. In 1840, he was appointed the chair of chemistry of the École Polytechnique, and in 1841, he became a professor of Physics in 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 n ...

. Beginning in 1843, he began compiling extensive numerical tables on the properties of steam. These were published in 1847, and led to his receiving the

Rumford Medal The Rumford Medal is an award bestowed by Britain's Royal Society every alternating year for "an outstandingly important recent discovery in the field of thermal or optical properties of matter made by a scientist working in Europe". First awar ...

of the

Royal Society of London The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, r ...

and appointment as

Chief Engineer of Mines Chief may refer to: Title or rank Military and law enforcement * Chief master sergeant, the ninth, and highest, enlisted rank in the U.S. Air Force and U.S. Space Force * Chief of police, the head of a police department * Chief of the boa ...

. In 1851 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 royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for prom ...

. In 1854 he was appointed director of the

porcelain Porcelain () is a ceramic material made by heating substances, generally including materials such as kaolinite, in a kiln to temperatures between . The strength and translucence of porcelain, relative to other types of pottery, arises main ...

works at

Sèvres Sèvres (, ) is a commune in the southwestern suburbs of Paris, France. It is located from the centre of Paris, in the Hauts-de-Seine department, Île-de-France region. The commune, which had a population of 23,251 as of 2018, is known for ...

, the ''

Manufacture nationale de Sèvres The ''Manufacture nationale de Sèvres'' is one of the principal European porcelain factories. It is located in Sèvres, Hauts-de-Seine, France. It is the continuation of Vincennes porcelain, founded in 1740, which moved to Sèvres in 1756. It ...

''. In 1855, he was elected to the

American Philosophical Society The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communit ...

. At Sèvres, he continued work on the thermal properties of matter. He designed sensitive

thermometer A thermometer is a device that measures temperature or a temperature gradient (the degree of hotness or coldness of an object). A thermometer has two important elements: (1) a temperature sensor (e.g. the bulb of a mercury-in-glass thermometer ...

hygrometer A hair tension dial hygrometer with a nonlinear scale. A hygrometer is an instrument used to measure the amount of water vapor in air, in soil, or in confined spaces. Humidity measurement instruments usually rely on measurements of some other q ...

s, hypsometers and

calorimeter A calorimeter is an object used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. Differential scanning calorimeters, isothermal micro calorimeters, titration calorimete ...

s, and measured the

specific heat In thermodynamics, the specific heat capacity (symbol ) of a substance is the heat capacity of a sample of the substance divided by the mass of the sample, also sometimes referred to as massic heat capacity. Informally, it is the amount of heat t ...

s of many substances and the

coefficient of thermal expansion Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including phase transitions. Temperature is a monotonic function of the average molecular kineti ...

of gases. In the course of this work, he discovered that not all gases expand equally when heated and that

Boyle's Law Boyle's law, also referred to as the Boyle–Mariotte law, or Mariotte's law (especially in France), is an experimental gas law that describes the relationship between pressure and volume of a confined gas. Boyle's law has been stated as: The ...

is only an approximation, especially at temperatures near a substance's boiling point. Regnault was also an avid amateur photographer. He introduced the use of

pyrogallic acid Pyrogallol is an organic compound with the formula C6H3(OH)3. It is a water-soluble, white solid although samples are typically brownish because of its sensitivity toward oxygen. It is one of three isomers of benzenetriols. Production and reac ...

as a developing agent, and was one of the first photographers to use paper negatives. In 1854, he became the founding president of the

Société française de photographie The Société française de photographie (SFP) is an association, founded on 15 November 1854, devoted to the history of photography. It has a large collection of photographs and old cameras. Among the founding members were Olympe Aguado, Hippoly ...

. In 1871, his laboratory at Sèvres was destroyed and his son Alex-Georges-Henri Regnault killed, both as a result of the Franco-Prussian War. He retired from science the next year, never recovering from these losses.

Legacy

The crater Regnault on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

is named after Regnault, and his name is one of the 72 names inscribed on the Eiffel Tower. Some have suggested that the symbol ''R'' for the

ideal gas constant The molar gas constant (also known as the gas constant, universal gas constant, or ideal gas constant) is denoted by the symbol or . It is the molar equivalent to the Boltzmann constant, expressed in units of energy per temperature increment per ...

is also named after him. He was the first president of

. The French ''Regnault'', built between 1913 and 1924 was named for him.

Works

* ''Regnault-Strecker's kurzes Lehrbuch der Chemie''. Vieweg, Braunschweig 185
Digital edition
by the

University and State Library Düsseldorf The University and State Library Düsseldorf (german: Universitäts- und Landesbibliothek Düsseldorf, abbreviated ULB Düsseldorf) is a central service institution of Heinrich Heine University. Along with Bonn and Münster, it is also one of t ...

*
2. Organische Chemie. 1853
*
1. Anorganische Chemie. 3., verb. Aufl. 1855
*
2. Organische Chemie. 2. Aufl.1857
*
1. Anorganische Chemie. 4. Aufl.1858
*
1. Anorganische Chemie. 9., neu bearb. Aufl. / von Johannes Wislicenus. 1877

References

{{DEFAULTSORT:Regnault, Henri Victor 1810 births 1878 deaths 19th-century French chemists 19th-century French physicists French Roman Catholics Thermodynamicists Collège de France faculty École Polytechnique alumni Mines ParisTech alumni Corps des mines People from Aachen People from the Rhine Province Foreign Members of the Royal Society Foreign associates of the National Academy of Sciences Members of the French Academy of Sciences Members of the Royal Swedish Academy of Sciences Corresponding members of the Saint Petersburg Academy of Sciences Recipients of the Pour le Mérite (civil class) Recipients of the Copley Medal 19th-century French photographers Recipients of the Matteucci Medal Members of the Royal Society of Sciences in Uppsala