Claude Louis Berthollet

(redirected from Berthollet)
Also found in: Medical.

Berthollet, Claude Louis


Born Dec. 9, 1748, in Talloires, Savoy; died Nov. 6,1822, in Paris. French chemist; founder of the study of chemical equilibrium. Member of the Paris Academy of Sciences (1785). Professor of chemistry at the Normal and Polytechnic schools in Paris (1794).

Having received the degree of doctor of medicine in Turin in 1770, Berthollet began to work in pharmacies; in 1772 he moved to Paris. In 1785 he was the first chemist to associate himself with the antiphlogiston views of A. Lavoisier. Together with Lavoisier and other scientists, Berthollet participated in the development of a new chemical nomenclature (1786–87) and in the founding (1789) of the journal Annales de chimie, which still exists.

During the Great French Revolution, Berthollet took an active part in organizing the production of saltpeter, steel, and other materials needed for the republic’s defense. In 1798–99 he participated in Bonaparte’s Egyptian expedition. In 1807, Berthollet founded a scientific society whose members included P. S. Laplace, A. Humboldt, J. B. Biot, D. F. Arago, and J. L. Gay-Lussac.

Particularly significant in Berthollet’s experimental work was his procedure for bleaching linen, wax, and paper with chlorine (1785) and the discovery, associated with this, of hypochlorite, chlorate, and Berthollet salt. Berthollet established that the direction of chemical reactions is determined by mass and the properties of the reacting substances and the conditions of the reaction. Proceeding from a view of the chemical reaction as a continuous and reversible process, Berthollet felt that the composition of the compounds formed during the process should change continuously, that is, should be variable. The French chemist J. L. Proust opposed this conclusion; he showed that the substances cited by Berthollet as examples of compounds of variable composition were in actuality mixtures and not chemical units. The controversy between Berthollet and Proust (1801–08) ended with the establishment of the law of definite proportions, which strengthened the position of the atomic theory in chemistry and concentrated the efforts of scientists on obtaining and investigating compounds of constant composition. At the start of the 20th century, N. S. Kurnakov discovered the existence of the chemically individual substances of variable composition foreseen by Berthollet. He named them berthollides in memory of Berthollet. This discovery resolved the contradiction between the seemingly incompatible views of Berthollet and Proust.


Recherches sur les lois de l’affinité. Paris, 1801.
Essai de statique chimique, vols. 1–2. Paris, 1803.


Kurnakov, N. S. Izbrannye trudy, vol. 1. Moscow, 1960.
Starosel’skaia-Nikitina, O. Ocherkipo istorii nauki i tekhniki perioda frantsuzskoi revoliutsii 1789–1794. Moscow-Leningrad, 1946.
Cuvier, G. Recueil des éloges historiques, vol. 3. Paris, 1827. Page 177.
Lemay, P., and R. E. Oesper. “Claude Louis Berthollet. “Journal of Chemical Education, 1946, vol. 23, no. 4, pp. 158–65 and no. 5, pp. 230–36.
Crosland, M. C. The Society of Arcueil. London, 1967.


References in periodicals archive ?
Berthollet said the forest road where the bodies were found is "often used by walkers".
Berthollet became ad joint chimiste del' Acadmie des Sciences in 1780, associe in 1785, pensionnaire in 1792, professeur de chimie at Ecole polytechnique in 1794, and membre de l'Institut de France in 1795.
Berthollet suggested the idea of an antagonistic force between acids and alkalis [5], resulting in reciprocal affinity.
In 1787, Berthollet showed by analysis that, surprisingly, prussic acid did not contain oxygen [5].
Technical and scientific investigations were said to be of equal interest to Berthollet [8], which probably explains why he was so active in the industrial area.
Together with fellow chemist and compatriot Jean Antoine Chaptal (1756-1832), who worked mainly on technical problems such as the production of alum and saltpeter, Berthollet pioneered the use of the decolourizing properties of oxymuriatic acid (chlorine) in the artificial bleaching of textiles [9], and launched that industry on a practical basis.
In 1784, Berthollet became the worthy successor of the conservative chemist Pierre Joseph Macquer (1718-1784) in the influential governmental post of director of the dyeing industry of France, a sector which had benefited directly from his own extensive research.
The mystery of chemical affinity presented a formidable challenge and Berthollet was intrigued by it.
If you're not looking for something too fancy, try the Htel des Allis, which is on 20 Rue Berthollet, at pounds 11 - pounds 20 per night.
Name Lifetime Andre Marie Ampere 1775-1836 Amedeo Avogadro 1776-1856 Claude-Louis Berthollet 1748-1822 Jons Jacob Berzelius 1779-1848 John Dalton 1776-1844 Humphry Davy 1778-1829 Louis Jacques Thenard 1775-1857 Table 3.
Last night, Chevaline's mayor Didier Berthollet said the forest road where the bodies were found is often used by walkers.
Last night, Chevaline's mayor Didier Berthollet confirmed the victims in the car were not local.