Lavoisier Antoine French chemist who, through a conscious revolution, became the father of modern chemistry. As a student, he stated "Iam young and avid for glory." He was educated in a radical tradition, a friend of Condillac and readMaquois's dictionary. He won a prize on lighting the streets of Paris, and designed a new method forpreparing saltpeter. He also married a young, beautiful 13-year-old girl named Marie-Anne, who translated from Englishfor him and illustrated his books. Lavoisier demonstrated with careful measurements that transmutation of water toearth was not possible, but that the sediment observed from boiling water came from the container. He burnt phosphorusand sulfur in air, and proved that the products weighed more than he original. Nevertheless, the weight gained was lostfrom 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 combineswith metals to form calxes. However, he tried to take credit for Priestley's discovery. Thistendency to use the results of others without acknowledgment then draw conclusions was characteristic of Lavoisier. InConsidérations Générales sur la Nature des Acides (1778), he demonstrated that the "air" responsible forcombustion was also the source of acidity. The next year, he named this portion oxygen (Greek for acid-former), and theother azote (Greek for no life). He also discovered that the inflammable air of Cavendish which he termedhydrogen (Greek for water-former), combined with oxygen to produce a dew, as Priestley had reported, whichappeared 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 (ElementaryTreatise of Chemistry, 1789) was the first modern chemical textbook, and presented a unified view of new theories ofchemistry, contained a clear statement of the Law of Conservation of Mass, and denied the existence of phlogiston. Inaddition, 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 theobservational basis of his chemistry, stating "I have tried...to arrive at the truth by linking up facts; tosuppress as much as possible the use of reasoning, which is often an unreliable instrument which deceives us, in orderto follow as much as possible the torch of observation and of experiment." Nevertheless, he believed that the realexistence of atoms was philosophically impossible. Lavoisier demonstrated that organisms disassemble and reconstituteatmospheric 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 foundthe same ratio for a flame and animals, indicating that animals produced energy by a type of combustion. Lavoisierbelieved in the radical theory, believing that radicals, which function as a single group in a chemical reaction, wouldcombine with oxygen in reactions. He believed all acids contained oxygen. He also discovered that diamond is acrystalline form of carbon. Lavoisier made many fundamental contributions to the science of chemistry. The revolutionin chemistry which he brought about was a result of a conscious effort to fit all experiments into the framework of asingle 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.