-
500 BCE
Leucippus: The Atomic Philosophy
Leucippus of Miletus is thought to have originated the atomic philosophy -
439 BCE
Democritus: The atomos (Atom).
Democritus of Abdera, named the building blocks of matter atomos, meaning literally “indivisible,” about 430 BCE -
Galileo's test of the Atomic Theory.
Galileo Galilei expressed his belief that vacuums can exist (1638), scientists began studying the properties of air and partial vacuums to test the relative merits of Aristotelian orthodoxy and the atomic theory. -
Boyle's systematic study of air.
Anglo-Irish chemist Robert Boyle began his systematic study of air in 1658 after he learned that Otto von Guericke, a German physicist and engineer, had invented an improved air pump four years earlier. -
Boyle published the Boyle's law.
In 1662 Boyle published the first physical law expressed in the form of an equation that describes the functional dependence of two variable quantities. This formulation became known as Boyle’s law. -
Mariotte's law
In France, Boyle’s law is called Mariotte’s law after physicist Edme Mariotte, who discovered the empirical relationship independently in 1676. -
Issac Newton expressed his views of the atom.
Isaac Newton expressed a typical 18th-century view of the atom that was similar to that of Democritus, Gassendi, and Boyle. In the last query in his book Opticks (1704) -
Bernoulli's the Kinetic Theory
-
Publication of the law of definite proportions (Proust's law)
In 1794 Joseph-Louis Proust of France published his law of definite proportions (also known as Proust’s law). -
John Dalton's book "A New System of Chemical Philosophy"
English chemist and physicist John Dalton extended Proust’s work and converted the atomic philosophy of the Greeks into a scientific theory between 1803 and 1808. His book A New System of Chemical Philosophy (Part I, 1808; Part II, 1810) was the first application of atomic theory to chemistry. -
Publication of Gay-Lussac's law
Gay-Lussac soon took the relationship between chemical masses implied by Dalton’s atomic theory and expanded it to volumetric relationships of gases. In 1809, he published two observations about gases that have come to be known as Gay-Lussac’s law of combining gases. -
The formulation of the Dulong-Petit law.
Proponents of the system used today based their chemical notation on an empirical law formulated in 1819 by the French scientists Pierre-Louis Dulong and Alexis-Thérèse Petit concerning the specific heat of elements. According to the Dulong-Petit law, the specific heat of all elements is the same on a per atom basis. -
Herapath's Kinethic Theory
-
Stanislao Cannizzaro revived Avogadro's ideas
Sicilian chemist Stanislao Cannizzaro revived Avogadro’s ideas in 1858 and expounded them at the First International Chemical Congress. -
Maxwell's paper, "Illustrations of the Dynamical Theory of Gases"
In his 1860 paper “Illustrations of the Dynamical Theory of Gases,” Maxwell used probability theory to produce his famous distribution function for the velocities of gas molecules. -
Mendeleyev's Periodic Table
Russian chemist Dmitry Ivanovich Mendeleyev based his system on the atomic weights of the elements as determined by Avogadro’s theory of diatomic molecules. In his paper of 1869 introducing the periodic law, he credited Cannizzaro for using “unshakeable and indubitable” methods to determine atomic weights.