GROUP3 Xyrill Cruz
                Monica Dayo
                Leslie Constantino
                Tish Darroca

Born: August 26, 1743

Birthplace: Paris, France

Died: May 8, 1794

He is known as the Father of Modern Chemistry. His real interest, however, was in science, which he pursued with passion while leading a full public life. On the basis of his earliest scientific work, mostly in geology, he was elected in 1768—at the early age of 25—to the Academy of Sciences, France's most elite scientific society. In the same year he bought into the Ferme Générale, the private corporation that collected taxes for the Crown on a profit-and-loss basis. A few years later he married the daughter of another tax farmer, Marie-Anne Pierrette Paulze, who was not quite 14 at the time. Madame Lavoisier prepared herself to be her husband's scientific collaborator by learning English to translate the work of British chemists like Joseph Priestley and by studying art and engraving to illustrate Antoine-Laurent's scientific experiments.

 The most important chemical reaction that he performed was decomposition of the red oxide of mercury to form metallic mercury and the gas he named oxygen. He was the first to weigh all the substances present before and after the reaction. On realization from his quantitative experiments was that when coal was burned, it united with oxygen to form carbon dioxide. Therefore, he concluded that respiration was related to combustion. He found that matter was conserved and its amount remained constant. Because of his findings, this lead to the Law of Conservation of Mass. This law states that matter is neither created nor destroyed during a chemical change. The total mass of the reaction products is always equal to the total mass of the reactants.

• Antoine Lavoisier, a French chemist, also discovered oxygen in 1775, was the first to recognize it as an element, and coined its name "oxygen" - which comes from a Greek word that means “acid-former”.
  
  
  

  

Antoine-Laurent Lavoisier conducts an experiment on human respiration in this drawing made by his wife, who depicted herself at the table on the far right. Courtesy Edgar Fahs Smith Memorial Collection, Department of Special Collections, University of Pennsylvania Library.

 

 

 

Analytical chemistry and chemical nomenclature

Lavoisier investigated the composition of water and air, which at the time were considered elements. He determined that the components of water were oxygen and hydrogen, and that air was a mixture of gases, primarily nitrogen and oxygen. With the French chemists Claude-Louis Berthollet, Antoine Fourcroy and Guyton de Morveau, Lavoisier devised a systematic chemical nomenclature. He described it in Méthode de nomenclature chimique (Method of Chemical Nomenclature, 1787). This system facilitated communication of discoveries between chemists of different backgrounds and is still largely in use today, including names such as sulfuric acid, sulfates, and sulfites.

Pioneer of stoichiometry

 

 

 

 

Laboratory equipment used by Lavoisier circa 1780s

 

Lavoisier's researches included some of the first truly quantitative chemical experiments. He carefully weighed the reactants and products in a chemical reaction, which was a crucial step in the advancement of chemistry. He showed that, although matter can change its state in a chemical reaction, the total mass of matter is the same at the end as at the beginning of every chemical change. Thus, for instance, if water is heated to steam, if salt is dissolved in water or if a piece of wood is burned to ashes, the total mass remains unchanged. His experiments supported the law of conservation of mass, which Lavoisier was the first to state,[2] although Mikhail Lomonosov (1711–1765) had previously expressed similar ideas in 1748 and proved them in experiments. Others who anticipated the work of Lavoisier include Joseph Black (1728–1799), Henry Cavendish (1731–1810), and Jean Rey (1583–1645).

 

 

 

 

 

 

 

The work of Lavoisier was translated in Japan in the 1840s, through the process of Rangaku. Page from Udagawa Yōan's 1840 Seimi Kaisō

 
 
 
 
 
 
 
 
 
LEGACY
 

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.

However, much to his professional detriment, Lavoisier discovered no new substances, devised no really novel apparatus, and worked out no improved methods of preparation. He was essentially a theorist, and his great merit lay in the capacity of taking over experimental work that others had carried out—without always adequately recognizing their claims—and by a rigorous logical procedure, reinforced by his own quantitative experiments, of expounding the true explanation of the results. He completed the work of Black, Priestley and Cavendish, and gave a correct explanation of their experiments.                                                                    Detail of picture of a combustion experiment

 

Overall, his contributions are considered the most important in advancing chemistry to the level reached in physics and mathematics during the 18th century.[8]

• Constant pressure calorimeter , engraving made by madame Lavoisier for thermochemistry experiments