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French chemist who, through a conscious revolution, became the
father of modern chemistry. As a student, he stated "I am young and
avid for glory." He was educated in a radical tradition, a friend of
Condillac
and read Maquois's
dictionary. He won a prize on lighting the streets of Paris, and
designed a new method for preparing saltpeter. He also married a
young, beautiful 13-year-old girl named Marie-Anne, who translated
from English for him and illustrated his books. Lavoisier
demonstrated with careful measurements that transmutation of water
to earth was not possible, but that the sediment observed from
boiling water came from the container. He burnt phosphorus and
sulfur in air, and proved that the products weighed more than he
original. Nevertheless, the weight gained was lost from the air.
Thus he established the Law of Conservation of Mass.
Repeating the experiments of Priestley,
he demonstrated that air is composed of two parts, one of which
combines with metals to form calxes. However, he tried to take
credit for Priestley's
discovery. This tendency to use the results of others without
acknowledgment then draw conclusions was characteristic of
Lavoisier. In Considérations Générales sur la Nature des
Acides (1778), he demonstrated that the "air" responsible for
combustion was also the source of acidity. The next year, he named
this portion oxygen (Greek for acid-former), and the other azote
(Greek for no life). He also discovered that the inflammable air of
Cavendish
which he termed hydrogen (Greek for water-former), combined with
oxygen to produce a dew, as Priestley
had reported, which appeared to be water.
In Reflexions sur le Phlogistique (1783), Lavoisier showed
the phlogiston theory to be inconsistent. In Methods of Chemical
Nomenclature (1787), he invented the system of chemical
nomenclature still largely in use today, including names such as
sulfuric acid, sulfates, and sulfites. His Traité Élémentaire de
Chimie (Elementary Treatise of Chemistry, 1789) was the first
modern chemical textbook, and presented a unified view of new
theories of chemistry, contained a clear statement of the Law of
Conservation of Mass, and denied the existence of phlogiston. In
addition, it contained a list of elements, or substances that could
not be broken down further, which included oxygen, nitrogen,
hydrogen, phosphorus, mercury, zinc, and sulfur. His list, however,
also included light,
 and caloric,
which
he believed to be material substances. In the work, Lavoisier
underscored the observational basis of his chemistry, stating "I
have tried...to arrive at the truth by linking up facts; to suppress
as much as possible the use of reasoning, which is often an
unreliable instrument which deceives us, in order to follow as much
as possible the torch of observation and of experiment."
Nevertheless, he believed that the real existence of atoms was
philosophically impossible. Lavoisier demonstrated that organisms
disassemble and reconstitute atmospheric air in the same manner as a
burning body.
With Laplace,
he used a calorimeter to estimate the heat evolved per unit of
carbon dioxide produced. They found the same ratio for a flame and
animals, indicating that animals produced energy by a type of
combustion. Lavoisier believed in the radical theory, believing that
radicals, which function as a single group in a chemical reaction,
would combine with oxygen in reactions. He believed all acids
contained oxygen. He also discovered that diamond is a crystalline
form of carbon. Lavoisier made many fundamental contributions to the
science of chemistry. The revolution in chemistry which he brought
about was a result of a conscious effort to fit all experiments into
the framework of a single theory. He established the consistent use
of chemical balance, used oxygen to overthrow the phlogiston theory,
and developed a new system of chemical nomenclature. He was beheaded
during the French revolution.
References
Berthelot, M. La révolution chimique: Lavoisier. Paris:
Alcan, 1890.
Daumas, M. Lavoisier, théoricien et expérimentateur.
Paris: Presses Universitaires de France, 1955.
Lavoisier, A. Traité élémentaire de chimie, présenté dans un
ordre nouveau et d'après les découvertes modernes, 2 vols.
Paris: Chez Cuchet, 1789. Reprinted Bruxelles: Cultures et
Civilisations, 1965.
Author: Eric W. Weisstein
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