Antoine Lavoisier
Antoine Lavoisier (1743-1794)
Antoine-Laurent Lavoisier (lah vwah ZYAY) was one
of the best-known French
scientists and was an important government official.
His theories of
combustion, his development of a way to classify the elements
and the first
modern textbook of chemistry led to his being known as the father
of modern
chemistry. He contributed to much of the research in the field of
chemistry.
He is quoted for saying, "Nothing is lost, nothing is created,
everything is
transformed." Lavoisier was born in Paris, France on Aug. 26,
1743. When
he was eleven years old he attended a college called Mazain.
For
Lavoisier's last two years in college he found a great deal of
interest in
science. He received an excellent education and developed an
interest in all
branches of science, especially chemistry. Abbe Nicolas Louis
de Lacaill taught
Lavoisier about meteorological observation. On 1763
Lavoisier received his
bachelor's degree and on 1764 a licentiate which
allowed him to practice his
profession. In his spare time he studied books
all about science. His 1st paper
was written about gypsum, also known by
hydrated calcium sulfate. He described
its chemical and physical properties.
He was elected to the French Academy of
Sciences in 1768. On 1771 he
married Marie Anne Pierrette Paulze. She helped
Lavoisier by drawing
diagrams for his scientific works and translating English
notation for him.
Unlike earlier chemists, Lavoisier paid particular attention
to the weight of
the ingredients involved in chemical reactions and of the
products that
resulted. He carefully measured the weights of the reactants and
products. He
noted that the weight of the air in which combustion occurred
decreases. He
found that when the burning material combined with the air somehow
and that
the air weighed less. Lavoisier found that the weight of the products
of
combustion equals the weight of the reacting ingredients. This
observation
became known as the law of conservation of mass (or matter). He
repeated many of
the experiments of earlier chemists but interpreted the
results far differently.
On 1772 he was studying on combustion, which he
is most known for in science.
Lavoisier presented an important memoir on
conversion of water into earth
evaporation. This brought him to the Oxygen
Theory of Combustion. On 1774
Lavoisier carried out experiments on
calcinations of tin and lead and confirmed
the increase of weight of metals
on calcinations from combustion of air. By
demonstrating the nature of
combustion, he disproved the phlogiston theory. The
phlogiston theory stated
that all flammable materials contained a substance
called phlogiston.
According to this theory, materials gave off phlogiston as
they burned. Air
was necessary for combustion because it absorbed the phlogiston
that was
released. This was thought at the time to be a fact. Lavoisier showed
this
theory to be false and made oxygen the reason that things burned,
not
phlogiston. Lavoisier burned textbooks that supported the theory. He was
trying
to make a point that the phlogiston theory was invalid and oxygen is
the new
answer to combustion. He laid the framework for understanding
chemical reactions
as combinations of elements to form new materials, or
products. He concluded
that combustion results from the rapid chemical union
of a flammable material
with a newly discovered gas, which he named "oxygen",
previously known
as "dephilogisticated air." The word "oxygen" means acid
producer.
Lavoisier and others had found that oxygen is a part of several
acids. Lavoisier
incorrectly reasoned that oxygen is needed to make all
acids. He developed
endings of the degree of oxygen by adding certain ending
such as -ic or -ous.
With French astronomer and mathematician Pierre
Simon Laplace, Lavoisier
conducted experiments on the respiration in animals.
Their studies showed a
similarity between ordinary chemical reactions and the
processes that happen in
living organisms. These experiments were the basis
for the science now known as
biochemistry. Lavoisier also helped to develop a
system for naming chemical
substances based on their composition. This system
is still in use. He made the
very first modern chemistry text named Traité
elémentaire de chimie (Elements
of Chemistry). Many consider it the first
textbook on modern chemistry. Here for
the first time the elements are laid
out systematically. His list included many
compounds, which were thought to
be elements at the time. Lavoisier worked out
reactions in chemical equations
that respect the conservation of mass. As a
government official, Lavoisier
was successful in creating agricultural reform,
serving as a tax collection
official, and overseeing the government's
manufacture of gunpowder. On 1775
he was made commissioner of gunpowder. He was
asked to improve the quality of
French gunpowder. This boosted his career.
Politically, Lavoisier was a
moderate constitutionalist, and Marat and other
radicals hated him because of
this. He became involved in the Ferme Generale, a
private tax-collection
firm, which became a target during the Terror. When the
Reign of Terror
erupted in France, Lavoisier fell victim to its tyranny and
France lost
one of her greatest scientist. The leaders of the French Revolution
arrested
Lavoisier in 1793. In spite of his achievements, Lavoisier was found
guilty
of conspiracy with the enemies of France because of his involvement in
tax
collection. Nov. 24, 1793 Lavoisier and his 27 other colleagues
were
guillotined.
Bibliography
http://www.english.upenn.edu/~jlynch/FrankDemo/People/lavois.html
1999 World
Book Encyclopedia
http://www.dupont.com/corp/science/lavoisier/antoine.html