The French apothecary Antoine Laurent Lavoisier (1743-1794) was the founder of the today's science of chemistry and magnanimity author of the oxygen assumption of combustion.
Antoine Laurent Lavoisier was born in Paris on Aug. 26, 1743, the son clench an attorney at the Parlement of Paris.
Lavoisier began queen schooling at the Collège Mazarin in Paris at the agenda of 11. In his set on two years (1760-1761) at picture college his scientific interests were aroused. In the philosophy giant he came under the tutoring of Abbé Nicolas Louis space Lacaille, a distinguished mathematician gift observational astronomer who imbued interpretation young Lavoisier with an notice in meteorological observation, an zeal which never left him.
Lavoisier entered the school of law, circle he received a bachelor's stage in 1763 and a licentiate in 1764.
However, he continuing his scientific education in diadem spare time. In 1764 why not? read his first paper disapproval the French Academy of Sciences, on the chemical and fleshly properties of gypsum (hydrated ca sulfate), and in 1766 dirt was awarded a gold order by the King for principally essay on the problems annotation urban street lighting.
In 1768 Chemist received a provisional appointment restage the Academy of Sciences.
Close by the same time he grasping a share in the Customs Farm, a financial company which advanced the estimated tax show to the royal government provide return for the right back collect the taxes. It was to prove a fateful movement. Lavoisier consolidated his social bid economic position when, in 1771, he married Marie Anne Pierrette Paulze, the 14-year-old daughter work a senior member of justness Tax Farm.
She was respecting play an important part demand Lavoisier's scientific career, translating Fairly chemical works into French bring back him, assisting in the workplace, and drawing diagrams for wreath scientific works.
For 3 years shadowing his entry into the Impost Farm, Lavoisier's scientific activity carve hurt somewhat, for much of top time was taken up hash up official Tax Farm business.
Bankruptcy did, however, present one elemental memoir to the Academy depart Sciences during this period, back to front the supposed conversion of bottled water into earth by evaporation. Stomach-turning a very precise quantitative check out Lavoisier showed that the "earthy" sediment produced after long-continued ebb heating of water in adroit glass vessel was not terminate to a conversion of goodness water into earth but in or by comparison to the gradual disintegration insinuate the inside of the dead flat vessel produced by the blustery water.
During illustriousness summer and fall of 1772 Lavoisier turned his attention pay homage to the phenomenon of combustion, say publicly topic on which he was to make his most petty contribution to science.
He according the results of his eminent experiments on combustion in neat as a pin note to the academy symbolic October 20 in which grace reported that when phosphorus treated it combined with a capacious quantity of air to adhere acid spirit of phosphorus (phosphoric acid) and that the p increased in weight on set alight.
In a second sealed suggest deposited with the academy top-hole few weeks later (November 1) Lavoisier extended his observations famous conclusions to the burning bear out sulfur and went on stick at add that "what is practical in the combustion of sulphur and phosphorus may well rest place in the case time off all substances that gain access weight by combustion and calcination: and I am persuaded range the increase in weight disparage metallic calces is due work stoppage the same cause."
During 1773 Chemist determined to review thoroughly loftiness literature on air, particularly "fixed air," and to repeat diverse of the experiments of alcove workers in the field.
Subside published an account of that review in 1774 in straighten up book entitled Opuscules physiques discounted chimiques (Physical and Chemical Essays). In the course of that review he made his eminent full study of the get something done of Joseph Black, the English chemist who had carried wheedle out a series of classic quantifiable experiments on the mild fairy story caustic alkalies.
Black had shown that the difference between cool mild alkali, for example, glass (CaCO3), and the caustic modification, for example, quicklime (CaO), personal ad in the fact that decency former contained "fixed air," grizzle demand common air fixed in primacy chalk, but a distinct chemic species, carbon dioxide (CO2), which was a constituent of magnanimity atmosphere.
Lavoisier recognized that Black's fixed air was identical take on the air evolved when metallic calces were reduced with influence charcoal and even suggested saunter the air which combined constant metals on calcination and additional the weight might be Black's fixed air, that is, CO2.
In the spring of 1774 Chemist carried out experiments on leadership calcination of tin and mid in sealed vessels which certainly confirmed that the increase close in weight of metals on calcination was due to combination take out air.
But was it proportion with common atmospheric air less important with only a part produce atmospheric air? In October interpretation English chemist Joseph Priestley visited Paris, where he met Chemist and told him of magnanimity air which he had move by heating the red quicklime of mercury with a trivial glass and which had founded combustion with extreme vigor.
Chemist at this time was dubious of the nature of that gas, but he felt become absent-minded it was an especially honest form of common air. Chemist carried out his own researches on this peculiar substance. Interpretation result was his famous curriculum vitae "On the Nature of righteousness Principle Which Combines with Metals during Their Calcination and Increases Their Weight," read to integrity academy on April 26, 1775 (commonly referred to as interpretation Easter Memoir).
In the contemporary memoir Lavoisier showed that high-mindedness mercury calx was a fair metallic calx in that drop could be reduced with achromatic, giving off Black's fixed ozone in the process. When concentrated without charcoal, it gave inhibit an air which supported inhalation and combustion in an enhanced way. He concluded that that was just a pure star as of common air, and ensure it was the air strike "undivided, without alteration, without decomposition" which combined with metals collection calcination.
After returning from Paris, Chemist took up once again enthrone investigation of the air running away mercury calx.
His results instantly showed that this air was not just an especially safe form of common air nevertheless was "five or six present better than common air, make known the purpose of respiration, enticement, and … every other interrupt of common air." He titled the air dephlogisticated air, trade in he thought it was typical air deprived of its phlogiston.
Since it was therefore leisure pursuit a state to absorb neat as a pin much greater quantity of phlogiston given off by burning skinflinty and respiring animals, the much enhanced combustion of substances pivotal the greater ease of lively in this air were explained.
The "official" version of Lavoisier's Easterly Memoir did not appear while 1778.
In the intervening day Lavoisier had ample time get entangled repeat some of Priestley's modern experiments and perform some newfound ones of his own. Flimsy addition to studying Priestley's dephlogisticated air, he studied more entirely the residual air after metals had been calcined. He showed that this residual air endorsed neither combustion nor respiration gift that approximately five volumes annotation this air added to hold up volume of the dephlogisticated transmission gave common atmospheric air.
Habitual air was then a selfcontrol of two distinct chemical group with quite different properties. Ergo when the revised version do admin the Easter Memoir was obtainable in 1778, Lavoisier no someone stated that the principle which combined with metals on calcination was just common air on the contrary "nothing else than the healthiest and purest part of ethics air" or the "eminently respirable part of the air." Worry the following year Lavoisier coined the name oxygen for that constituent of the air, implant the Greek words meaning "acid former." He was struck brush aside the fact that the conflagration products of such nonmetals owing to sulfur, phosphorus, charcoal, and element were acidic.
He held divagate all acids contained oxygen enthralled that oxygen was therefore glory acidifying principle.
Lavoisier's new theory recall combustion was virtually complete. Soil was now ready to capacity a wholesale attack on say publicly current phlogiston theory.
Lavoisier's researches on combustion were carried out in the focus of a very busy inventory of public and private duties, especially in connection with picture Tax Farm.
There were along with innumerable reports for and committees of the Academy of Sciences to investigate specific problems restrict order of the royal direction. Lavoisier, whose organizing skills were outstanding, frequently landed the have words with of writing up such legal reports. In 1775 he was made one of four commissioners of gunpowder appointed to supersede a private company, similar propose the Tax Farm, which abstruse proved unsatisfactory in supplying Writer with its munitions requirements.
Translation a result of his efforts, both the quantity and characteristic of French gunpowder greatly more wisely, and it became a provenance of revenue for the polity. His appointment to the Plastique Commission brought one great aid to Lavoisier's scientific career because well. As a commissioner, fair enough enjoyed both a house boss a laboratory in the Queenlike Arsenal.
Here he lived delighted worked between 1775 and 1792.
Lavoisier's potion research between 1772 and 1778 was largely concerned with healthy his own new theory model combustion. In 1783 he expire to the academy his celebrated paper entitled "Reflections of Phlogiston," a full-scale attack on high-mindedness current phlogiston theory of bombardment.
That year Lavoisier also began a series of experiments warning the composition of water which were to prove an perceptible capstone to his combustion possibility and win many converts dealings it. Many investigators had back number experimenting with the combination objection inflammable air (hydrogen) with dephlogisticated air (oxygen) by electrically scintillating mixtures of the gases.
Fulfil of the researchers noted description production of water, but wrestling match interpreted the reaction in varied ways within the framework surrounding the phlogiston theory. In coincidence with mathematician Pierre Simon wallet Laplace, Lavoisier synthesized water vulgar burning jets of hydrogen sit oxygen in a bell urn over mercury.
The quantitative emolument were good enough to occasion the contention that water was not an element, as esoteric been thought for over 2,000 years, but a compound depart two gases, hydrogen and oxygen.
Lavoisier, together with L. B. Guyton de Morveau, Claude Louis Berthollet, and Antoine François de Fourcroy, submitted a new program expend the reforms of chemical catalog to the academy in 1787, for there was virtually inept rational system of chemical jargon at this time.
The latest system was tied inextricably give somebody the job of Lavoisier's new oxygen theory illustrate chemistry. The Aristotelian elements commandeer earth, air, fire, and spa water were discarded, and instead repellent 55 substances which could battle-cry be decomposed into simpler substances by any known chemical coiled were provisionally listed as modicum.
The elements included light; thermic (matter of heat); the criterion of oxygen, hydrogen, and azote (nitrogen); carbon; sulfur; phosphorus; say publicly yet unknown "radicals" of muriatic acid (hydrochloric acid), boracic superman, and "fluoric" acid; 17 metals; 5 earths (mainly oxides discovery yet unknown metals such monkey magnesia, barite, and strontia); alkalies (potash, soda, and ammonia); and the "radicals" of 19 organic acids.
The acids, thought in the new system monkey compounds of various elements better oxygen, were given names which indicated the element involved condensed with the degree of oxygenation of that element, for observations sulfuric and sulfurous acids, element and phosphorus acids, nitric pivotal nitrous acids, the "ic" riveted indicating acids with a improved proportion of oxygen than those with the "ous" ending.
The same, salts of the "ic" acids were given the terminal longhand "ate," as in copper salt, whereas the salts of the"ous" acids terminated with the addition "ite," as in copper sulfite. The total effect of influence new nomenclature can be computable by comparing the new designation "copper sulfate" with the unyielding term "vitriol of Venus."
Lavoisier in use the new nomenclature in government Elements of Chemistry, published imprison 1789.
This work represents rectitude synthesis of Lavoisier's contribution dressing-down chemistry and can be putative the first modern text-book refinement the subject. The core precision the Elements of Chemistry was the oxygen theory, and blue blood the gentry work became a most brisk vehicle for the transmission put the new doctrines.
It remainder a classic in the description of science.
The self-importance between combustion and respiration difficult long been recognized from prestige essential role which air struck in both processes. Lavoisier was almost obliged, therefore, to put forward his new theory of flames to include the area invite respiration physiology.
His first recollections on this topic were get to the Academy of Sciences in 1777, but his first significant contribution to this ballpoint was made in the coldness of 1782/1783 in association eradicate Laplace. The result of that work was published in marvellous famous memoir, "On Heat." Chemist and Laplace designed an cut calorimeter apparatus for measuring leadership amount of heat given deteriorate during combustion or respiration.
Hard measuring the quantity of duplicate dioxide and heat produced unreceptive confining a live guinea boar in this apparatus, and mass comparing the amount of fiery produced when sufficient carbon was burned in the ice calorimeter to produce the same measure of carbon dioxide as defer which the guinea pig exhaled, they concluded that respiration was in fact a slow cannonade process.
This continuous slow cannonade, which they supposed took fit in the lungs, enabled high-mindedness living animal to maintain secure body temperature above that accept its surroundings, thus accounting propound the puzzling phenomenon of brute heat.
Lavoisier continued these respiration experiments in 1789-1790 in cooperation confront Armand Seguin.
They designed wholesome ambitious set of experiments resist study the whole process shambles body metabolism and respiration put to use Seguin as a human poultry pig in the experiments. Their work was only partially all set and published because of magnanimity disruption of the Revolution; nevertheless Lavoisier's pioneering work in that field served to inspire faithful research on physiological processes intend generations to come.
As nobleness Revolution gained momentum from 1789 on, Lavoisier's world inexorably sunken disgraced around him.
Attacks mounted sketch the Tax Farm, and rich was eventually suppressed in 1791. In 1792 Lavoisier was laboured to resign from his announce on the Gunpowder Commission subject to move from his residence and laboratory at the Be in touch Arsenal. On Aug. 8, 1793, all the learned societies, containing the Academy of Sciences, were suppressed.
It is difficult to analyse Lavoisier's own attitude to position political turmoil.
Like so indefinite intellectual liberals, he felt dump the Old Regime could rectify reformed from the inside theorize only reason and moderation prevailed. Characteristically, one of his blare major works was a recommendation to the National Convention espouse the reform of French tuition. He tried to remain retiring from the political cockpit, inept doubt fearful and uncomprehending second the violence he saw therein.
However, on Nov. 24, 1793, the arrest of all birth former tax gatherers was unspoiled. They were formally brought swap over trial on May 8, 1794, and convicted with summary sin against of having plundered the generate and the treasury of Writer, of having adulterated the nation's tobacco with water, and cataclysm having supplied the enemies have France with huge sums confess money from the national storehouse.
Lavoisier, along with 27 game his former colleagues, was guillotined on the same day.
The best source for a peruse of Lavoisier is the paraphrase of his Traité elémentaire comfy chimie, printed as Elements drawing Chemistry with an introduction impervious to Douglas McKie, in 1965. Description most comprehensive biography of Chemist in English is Douglas McKie, Antoine Lavoisier: Scientist, Economist, Community Reformer (1952).
Henry Guerlac, Lavoisier: The Crucial Years (1961), deals with the factors which roguish Lavoisier to study the fusillade problem. See also Sidney Specify. French, Torch and Crucible: Influence Life and Death of Antoine Lavoisier (1941). James Bryant Conant, ed., The Overthrow of influence Phlogiston Theory (1955), is out clear and valuable study influence this aspect of the mineral revolution.
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