Antoine lavoisier

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1. Antoine Lavoisier

Antoine-Laurent de Lavoisier



Antoine-Laurent de Lavoisier (also Antoine Lavoisier after
the French Revolution; 26 August 1743 – 8 May 1794; French
pronunciation: [ɑ̃twan lɔʁɑ̃ də lavwazje]) was a French nobleman and
chemist central to the 18th-century chemical revolution and had a large
influence on both the history of chemistry and the history of biology. He

2. is widely considered in popular literature as the "father of modern
chemistry". This label, however, is more a product of Lavoisier's
eminent skill as a self-promoter and underplays his dependence on the
instruments, experiments, and ideas of other chemists
It is generally accepted that Lavoisier's great accomplishments
in chemistry largely stem from his changing the science from a
qualitative to a quantitative one. Lavoisier is most noted for his
discovery of the role oxygen plays in combustion. He recognized and
named oxygen (1778) and hydrogen (1783) and opposed the phlogiston
theory. Lavoisier helped construct the metric system, wrote the first
extensive list of elements, and helped to reform chemical nomenclature.
He predicted the existence of silicon (1787) and was also the first to
establish that sulfur was an element (1777) rather than a compound. He
discovered that, although matter may change its form or shape, its mass
always remains the same.
Lavoisier was a powerful member of a number of aristocratic
councils, and an administrator of the Ferme Générale. The Ferme
general was one of the most hated components of the Ancien Régime
because of the profits it took at the expense of the state, the secrecy of
the terms of its contracts, and the violence of its armed agentsAll of
these political and economic activities enabled him to fund his scientific
research. At the height of the French Revolution, he was accused by
Jean-Paul Marat of selling adulterated tobacco and of other crimes, and
was eventually guillotined a year after Marat's death.
Biography
Early life and education
Antoine-Laurent Lavoisier was born to a wealthy family in Paris
on 26 August 1743. The son of an attorney at the Parliament of Paris, he
inherited a large fortune at the age of five with the passing of his mother

3. Lavoisier began his schooling at the Collège des Quatre-Nations,
University of Paris, (known as the Collège Mazarin) in Paris in 1754 at
the age of 11. In his last two years (1760–1761) at the school, his
scientific interests were aroused, and he studied chemistry, botany,
astronomy, and mathematics. In the philosophy class he came under the
tutelage of Abbé Nicolas Louis de Lacaille, a distinguished
mathematician and observational astronomer who imbued the young
Lavoisier with an interest in meteorological observation, an enthusiasm
which never left him. Lavoisier entered the school of law, where he
received a bachelor's degree in 1763 and a licentiate in 1764. Lavoisier
received a law degree and was admitted to the bar, but never practiced as
a lawyer. However, he continued his scientific education in his spare
time.
Early scientific work

Lavoisier's education was filled with the ideals of the French
Enlightenment of the time, and he was fascinated by Pierre Macquer's
dictionary of chemistry. He attended lectures in the natural sciences.
Lavoisier's devotion and passion for chemistry were largely influenced
by Étienne Condillac, a prominent French scholar of the 18th century.
His first chemical publication appeared in 1764. From 1763 to 1767, he
studied geology under Jean-Étienne Guettard. In collaboration with
Guettard, Lavoisier worked on a geological survey of Alsace-Lorraine in
June 1767. In 1764 he read his first paper to the French Academy of
Sciences, France's most elite scientific society, on the chemical and
physical properties of gypsum (hydrated calcium sulfate), and in 1766 he
was awarded a gold medal by the King for an essay on the problems of
urban street lighting. In 1768 Lavoisier received a provisional
appointment to the Academy of Sciences. In 1769, he worked on the
first geological map of France.

4. Ferme générale and marriage




Portrait of Antoine-Laurent Lavoisier and his wife by Jacques-Louis
David, ca. 1788
At the age of 26, around the time he was elected to the
Academy of Sciences, Lavoisier bought a share in the Ferme générale, a
tax farming financial company which advanced the estimated tax
revenue to the royal government in return for the right to collect the
taxes. Lavoisier attempted to introduce reforms in the French monetary
and taxation system to help the peasants. While in government work, he
helped develop the metric system to secure uniformity of weights and
measures throughout France.
Lavoisier consolidated his social and economic position
when, in 1771 at age 28, he married Marie-Anne Pierrette Paulze, the
13-year-old daughter of a senior member of the Ferme générale. She
was to play an important part in Lavoisier's scientific career—notably,

5. she translated English documents for him, including Richard Kirwan's
Essay on Phlogiston and Joseph Priestley's research. In addition, she
assisted him in the laboratory and created many sketches and carved
engravings of the laboratory instruments used by Lavoisier and his
colleagues for their scientific works.
Madame Lavoisier edited and published Antoine's memoirs
(whether any English translations of those memoirs have survived is
unknown as of today) and hosted parties at which eminent scientists
discussed ideas and problems related to chemistry. For 3 years following
his entry into the Ferme générale, Lavoisier's scientific activity
diminished somewhat, for much of his time was taken up with official
Ferme générale business. He did, however, present one important
memoir to the Academy of Sciences during this period, on the supposed
conversion of water into earth by evaporation. By a very precise
quantitative experiment Lavoisier showed that the "earthy" sediment
produced after long-continued reflux heating of water in a glass vessel
was not due to a conversion of the water into earth but rather to the
gradual disintegration of the inside of the glass vessel produced by the
boiling water.
Oxygen theory of combustion



Antoine Lavoisier's famous phlogiston experiment. Engraving
by Mme Lavoisier in the 1780s taken from Traité élémentaire de chimie
(Elementary treatise on chemistry)

6. During late 1772 Lavoisier turned his attention to the phenomenon of
combustion, the topic on which he was to make his most significant
contribution to science. He reported the results of his first experiments
on combustion in a note to the Academy on 20 October, in which he
reported that when phosphorus burned, it combined with a large quantity
of air to produce acid spirit of phosphorus, and that the phosphorus
increased in weight on burning. In a second sealed note deposited with
the Academy a few weeks later (1 November) Lavoisier extended his
observations and conclusions to the burning of sulfur and went on to add
that "what is observed in the combustion of sulfur and phosphorus may
well take place in the case of all substances that gain in weight by
combustion and calcination: and I am persuaded that the increase in
weight of metallic calces is due to the same cause.
Chemical nomenclature



Lavoisier's Laboratory, Musée des Arts et Métiers, Paris.

7. Lavoisier and Berthollet, Chimistes Celebres, Liebig's Extract of Meat
Company Trading Card, 1929
Lavoisier, together with L. B. Guyton de Morveau,
Claude-Louis Berthollet, and Antoine François de Fourcroy, submitted a
new program for the reforms of chemical nomenclature to the Academy
in 1787, for there was virtually no rational system of chemical
nomenclature at this time. The new system was tied inextricably to
Lavoisier's new oxygen theory of chemistry.
The Classical elements of earth, air, fire, and water were
discarded, and instead some 55 substances which could not be
decomposed into simpler substances by any known chemical means
were provisionally listed as elements. The elements included light;
caloric (matter of heat); the principles of oxygen, hydrogen, and azote
(nitrogen); carbon; sulfur; phosphorus; the yet unknown "radicals" of
muriatic acid (hydrochloric acid), boracic acid, and "fluoric" acid; 17
metals; 5 earths (mainly oxides of yet unknown metals such as
magnesia, barite, and strontia); three alkalies (potash, soda, and
ammonia); and the "radicals" of 19 organic acids. The acids, regarded in
the new system as compounds of various elements with oxygen, were
given names which indicated the element involved together with the
degree of oxygenation of that element, for example sulfuric and
sulfurous acids, phosphoric and phosphorus acids, nitric and nitrous
acids, the "ic" termination indicating acids with a higher proportion of
oxygen than those with the "ous" ending. Similarly, salts of the "ic"

8. acids were given the terminal letters "ate," as in copper sulfate, whereas
the salts of the "ous" acids terminated with the suffix "ite," as in copper
sulfite. The total effect of the new nomenclature can be gauged by
comparing the new name "copper sulfate" with the old term "vitriol of
Venus." Lavoisier described this system of nomenclature in Méthode de
nomenclature chimique (Method of Chemical Nomenclature, 1787).
Elementary Treatise of Chemistry
Lavoisier employed the new nomenclature in his Traité
élémentaire de chimie (Elementary Treatise on Chemistry), published in
1789. This work represents the synthesis of Lavoisier's contribution to
chemistry and can be considered the first modern textbook on the
subject.
The core of the work was the oxygen theory, and the work
became a most effective vehicle for the transmission of the new
doctrines. It 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. This text clarified the concept of an
element as a substance that could not be broken down by any known
method of chemical analysis, and presented Lavoisier's theory of the
formation of chemical compounds from elements
It remains a classic in the history of science. While many
leading chemists of the time refused to accept Lavoisier's new ideas,
demand for Traité élémentaire as a textbook in Edinburgh was sufficient
to merit translation into English within about a year of its French
publication. In any event, the Traité élémentaire was sufficiently sound
to convince the next generation.

9. Lavoisier conducting an experiment on respiration in the 1770s
Physiological work

Constant-pressure calorimeter, engraving made by madame Lavoisier
for thermochemistry experiments
The relationship between combustion and respiration had
long been recognized from the essential role which air played in both
processes. Lavoisier was almost obliged, therefore, to extend his new
theory of combustion to include the area of respiration physiology. His
first memoirs on this topic were read to the Academy of Sciences in
1777, but his most significant contribution to this field was made in the
winter of 1782/1783 in association with Laplace. The result of this work
was published in a famous memoir, "On Heat." Lavoisier and Laplace
designed an ice calorimeter apparatus for measuring the amount of heat
given off during combustion or respiration. The outer shell of the
calorimeter was packed with snow, which melted to maintain a constant
temperature of 0 °C around an inner shell filled with ice.
By measuring the quantity of carbon dioxide and heat produced
by confining a live guinea pig in this apparatus, and by comparing the
amount of heat produced when sufficient carbon was burned in the ice
calorimeter to produce the same amount of carbon dioxide as that which
the guinea pig exhaled, they concluded that respiration was in fact a
slow combustion process. Lavoisier stated, "la respiration est donc une

10. combustion," that is, respiratory gas exchange is a combustion, like that
of a candle burning.
This continuous slow combustion, which they supposed took
place in the lungs, enabled the living animal to maintain its body
temperature above that of its surroundings, thus accounting for the
puzzling phenomenon of animal heat. Lavoisier continued these
respiration experiments in 1789–1790 in cooperation with Armand
Seguin. They designed an ambitious set of experiments to study the
whole process of body metabolism and respiration using Seguin as a
human guinea pig in the experiments. Their work was only partially
completed and published because of the disruption of the Revolution;
but Lavoisier's pioneering work in this field served to inspire similar
research on physiological processes for generations to come.
Final days and execution
As the French Revolution gained momentum from 1789 on,
Lavoisier's world inexorably collapsed around him. Attacks mounted on
the deeply unpopular Ferme Générale, and it was eventually suppressed
in 1791. In 1792 Lavoisier was forced to resign from his post on the
Gunpowder Commission and to move from his house and laboratory at
the Royal Arsenal. On 8 August 1793, all the learned societies, including
the Academy of Sciences, were suppressed.
It is difficult to assess Lavoisier's own attitude to the political
turmoil. Like so many intellectual liberals, he felt that the Ancien
Régime could be reformed from the inside if only reason and moderation
prevailed. Characteristically, one of his last major works was a proposal
to the National Convention for the reform of French education. He tried
to remain aloof from the political cockpit, no doubt fearful and
uncomprehending of the violence he saw therein. However, on 24
November 1793, the arrest of all the former tax gatherers was ordered.
He was branded a traitor by the Convention under Maximilien de
Robespierre during the Reign of Terror, in 1794. He had also intervened

11. on behalf of a number of foreign-born scientists including
mathematician Joseph Louis Lagrange, which helped to exempt them
from a mandate stripping all foreigners of possessions and freedom.
Lavoisier was tried, convicted, and guillotined on 8 May 1794 in Paris,
at the age of 50, along with his 27 co-defendants.
According to a (probably apocryphal) story, the appeal to
spare his life so that he could continue his experiments was cut short by
the judge: "La République n'a pas besoin de savants ni de chimistes ; le
cours de la justice ne peut être suspendu." ("The Republic needs neither
scientists nor chemists; the course of justice cannot be delayed.")
Lavoisier was convicted with summary justice of having plundered the
people and the treasury of France, of having adulterated the nation's
tobacco with water, and of having supplied the enemies of France with
huge sums of money from the national treasury.
Lavoisier's importance to science was expressed by Joseph Louis
Lagrange who lamented the beheading by saying: "Il ne leur a fallu
qu’un moment pour faire tomber cette tête, et cent années peut-être ne
suffiront pas pour en reproduire une semblable." ("It took them only an
instant to cut off this head, and one hundred years might not suffice to
reproduce its like.")

12. Post-mortem





Statue of Lavoisier, at Hôtel de Ville, Paris
A year and a half after his death, Lavoisier was exonerated by the
French government. When his private belongings were delivered to his
widow, a brief note was included, reading "To the widow of Lavoisier,
who was falsely convicted"
About a century after his death, a statue of Lavoisier was erected
in Paris. It was later discovered that the sculptor had not actually copied
Lavoisier's head for the statue, but used a spare head of the Marquis de
Condorcet, the Secretary of the Academy of Sciences during Lavoisier's
last years. Lack of money prevented alterations from being made. The
statue was melted down during the Second World War and has not since
been replaced.

13. However, one of the main "lycées" (high schools) in Paris and a
street in the 8th arrondissement are named after Lavoisier, and statues of
him are found on the Hôtel de Ville and on the façade of the Cour
Napoléon of the Louvre. His name is one of the 72 names of eminent
French scientists, engineers and mathematicians inscribed on the Eiffel
Tower as well as on buildings around Killian Court at MIT in
Cambridge, MA US.
Lavoisier is listed among eminent Roman Catholic scientists,
and as such he defended his faith against those who attempted to use
science to attack it. Louis Edouard Grimaux, author of the standard
French biography of Lavoisier, and the first biographer to obtain access
to Lavoisier's papers, writes the following:
Raised in a pious family which had given many priests to the
Church, he had held to his beliefs. To Edward King, an English author
who had sent him a controversial work, he wrote, "You have done a
noble thing in upholding revelation and the authenticity of the Holy
Scripture, and it is remarkable that you are using for the defense
precisely the same weapons which were once used for the attack".
Legacy

14. The work of Lavoisier was translated in Japan in the 1840s, through the
process of Rangaku. Page from Udagawa Yōan's 1840 Seimi Kaisō
Lavoisier's fundamental contributions to chemistry were a
result of a conscious effort to fit all experiments into the framework of a
single theory. He established the consistent use of the chemical balance,
used oxygen to overthrow the phlogiston theory, and developed a new
system of chemical nomenclature which held that oxygen was an
essential constituent of all acids (which later turned out to be erroneous).
Lavoisier also did early research in physical chemistry and
thermodynamics in joint experiments with Laplace. They used a
calorimeter to estimate the heat evolved per unit of carbon dioxide
produced, eventually finding the same ratio for a flame and animals,
indicating that animals produced energy by a type of combustion
reaction.
Lavoisier also contributed to early ideas on composition and
chemical changes by stating the radical theory, believing that radicals,
which function as a single group in a chemical process, combine with
oxygen in reactions. He also introduced the possibility of allotropy in
chemical elements when he discovered that diamond is a crystalline
form of carbon.
He was essentially a theorist, and his great merit lay in his
capacity to take over experimental work that others had carried out—
without always adequately recognizing their claims—and by a rigorous
logical procedure, reinforced his own quantitative experiments,
expounding the true explanation of the results. He completed the work
of Black, Priestley and Cavendish, and gave a correct explanation of
their experiments.
Overall, his contributions are considered the most important in
advancing chemistry to the level reached in physics and mathematics
during the 18th century. Lavoisier's work was recognized as an
International Historic Chemical Landmark by the American Chemical

15. Society, Académie des sciences de L'institut de France and the Société
Chimique de France in 1999.