Chemistry Timeline

Early years

Prior to the acceptance of the scientific method in the 1600's and its application to the field of chemistry, it is somewhat controversial to consider many of the people listed below as "chemists" in the modern sense of the world. However, the ideas of certain great thinkers, either for their prescience, or for their wide and long-term acceptance, bears listing here.

c. 3000 BCE: Egyptians formulated the theory of the Ogdoad the “primordial forces”, from which all was formed; these were the elements of chaos, numbered in eight, that existed before the creation of the sun.

c. 1900 BCE: Hermes Trismegistus, a great Egyptian adept king, is thought to have founded of the art of alchemy.

c. 1500 BCE: the world's first chemist ‘Tapputi’ the perfume-maker was mentioned in a cuneiform tablet in Mesopotamia.

c. 450 BCE: Empedocles - assertes that all things are composed of four primal elements: earth, air, fire, and water, whereby two active and opposing forces, love and hate, or affinity and antipathy, act upon these elements, combining and separating them into infinitely varied forms.

c. 440 BCE: Leucippus and Democritus - Proposes idea of the atom, an indivisible particle that all matter is made of. This idea is largely rejected by natural philosophers in favor of the Aristotlean view.

c. 350 BCE: Aristotle - Based on the ideas of Empedocles, proposes idea of a substance as a combination of matter and form. Describes theory of the Five Elements which is largely accepted throughout the western world for over 1000 years. 50 BCE: Lucretius - Publishes De Rerum Natura, a poetic description of the ideas of Atomism.

c. 770: Abu Musa Jabir ibn Hayyan (aka Geber) - Isolation of numerous acids, including hydrochloric acid, nitric acid, citric acid, acetic acid, tartaric acid, and aqua regia.

c. 900: Abū Bakr Muhammad ibn Zakarīya al-Rāzi (aka Rhazes) - Publishes several treatises on alchemy, including some of the earliest descriptions of controlled distillation and extraction methods. He also developed early method for the production of sulfuric acid.

c. 1220: Robert Grosseteste - Publishes several Aristotelian commentaries where he lays out an early framework for the Scientific Method.

c. 1265: Roger Bacon - Publishes Opus Maius, which among other things, proposes an early form of the Scientific Method, and contains results of his experiments with gunpowder.

c. 1310: Pseudo-Geber - Anonymous Spanish alchemist publishes several books that establish the well-held theory that all metals were composed of various proportions of sulfur and mercury.

17th and 18th centuries

1605: Sir Francis Bacon - Publishes The Proficience and Advancement of Learning, which proposes a scheme credited with being the first description of what would later be known as the scientific method.

1605: Michał Sędziwój - Publishes the alchemical treatise A New Light of Alchemy which proposed the existance of the "food of life" within air, much later recognized as oxygen

1637: René Descartes - Publishes Discours de la méthode, which contains an outline of the scientific method.

1648: Johann Baptista van Helmont - Posthumous publication of his book Ortus medicinae which is cited by some as a major transitional work between alchemy and chemistry, and as an important influence on Robert Boyle. The book contains numerous experiments where, among other things, isolated numerous gaseous products from various chemical reactions, and establishes an early version of the Law of conservation of mass when he notes that the dissolution of metals by an acid did not represent their destruction, as such metals could be reproduced.

1661: Robert Boyle - The Sceptical Chymist - Treatise on the disctinction between chemistry and alchemy, contained ideas of atoms, molecules, and of chemical reactions

1662: Robert Boyle - Boyle's Law - first description of the behavior of gases, specifically the relationship between pressure and volume

1754: Joseph Black - isolation of carbon dioxide, which he called "fixed air".

1758: Joseph Black - formulates concept of latent heat to explain the thermochemistry of phase changes.

1773-1774: Carl Wilhelm Scheele and Joseph Priestly - isolation of oxygen, called by Priestly "dephlogisticated air" and Scheele "fire air".

1778: Antoine Lavoisier - Recognized and named oxygen, recognized its importance and role in combustion.

1787: Antoine Lavoisier - Publishes Méthode de nomenclature chimique , the first modern system of chemical nomenclature.

1787: Jacques Charles - Charles's Law - corrolary of Boyle's Law, describes relationship between temperature and volume of a gas.

1789: Antoine Lavoisier - Publishes Traité Élémentaire de Chimie, the first modern chemistry textbook, gave a complete survey of (at that time) modern chemistry, including the first concise definition of the law of conservation of mass, and thus the founding of the discipline of stoichiometry or quantitative chemical analysis.

1797: Joseph Proust - Law of definite proportions states that elements always combine in small, whole number ratios to form compounds.

1800: Alessandro Volta - Devises the first chemical battery, thereby founding the discipline of electrochemistry.


19th century

1802-1805: Joseph Louis Gay-Lussac - collects and discovers several chemical and physical properties of air and of other gases, including experimental proofs of Boyle's and Charles's laws, and of relationships between density and composition of gases. Also discovers that water is composed of two parts hydrogen and one part oxygen (H2O), instead of HO as previously thought.

1803: John Dalton - Dalton's Law describes relationship between pressure and makeup of gases.
1807-1808: Sir Humphry Davy - Use of electrolysis to isolate numerous elements, including potassium, sodium, calcium, strontium, barium, chlorine and the first discovery of aluminum.

1808: John Dalton - Publishes New System of Chemical Philosophy, which contains first modern scientific description of the atomic theory, and clear description of the law of multiple proportions.

1808: Jöns Jakob Berzelius - Published Lärboki Kemien in which he nvented modern chemical symbols and notation, developed concept of relative atomic weight.

1811: Amedeo Avogadro - Avogadro's law - Equal volumes of gases contain equal numbers of particles.

1815: William Prout - Prout's hypothesis proposes that all elements are conglomerations of hydrogen. Later disproven, though the near equivalence of the masses of protons and neutrons can explain the popularity of it.

1825: Michael Faraday - isolates benzene, the first isolated aromatic hydrocarbon.

1825: Friedrich Wöhler and Justus von Liebig - First confirmed discovery and explanation of isomers, earlier named by Berzelius. Working with cyanic acid and fulminic acid, they correctly deduced that isomerism was caused by differing arrangements of atoms.

1828: Friedrich Wöhler - Synthesized urea, thereby establishing that organic compounds could be produced from inorganic starting materials, disproving the theory of vitalism.

1832: Friedrich Wöhler and Justus von Liebig - Discovery and explanation of functional groups and of radicals in organic chemistry.

1840: Germain Hess - Hess's Law, an early statement of the Law of conservation of energy establishes that energy changes in a chemical process depend only on the states of the starting and product materials and not on the specific pathway taken between the two states.

1847: Hermann Kolbe - Obtains acetic acid from completely inorganic sources.

1848: Lord Kelvin - Establishes concept of absolute zero, the temperature at which all molecular motion ceases.

1849: Louis Pasteur - Discovers chirality and in tartaric acid, starting the study of stereochemistry.

1852: August Beer - Beer's law explains the relationship between the composition of a mixture and the amount of light it will absorb. Based partly on earlier work by Pierre Bouguer and Johann Heinrich Lambert, it establishes the analytical technique known as spectrophotometry.

1855: Benjamin Silliman, Jr. - Pioneers methods of petroleum cracking, which makes the entire modern petrochemical industry possible.

1856: William Henry Perkin - Perkin's mauve, an early synthetic dye, starts the dye manufacturing industry, one of the first commercially successful chemical industries.

1856: Alexander Parkes - Parkesine, one of the earliest synthetic polymers, is developed.

1857: Friedrich August Kekulé von Stradonitz - Proposed that carbon was tetravalent, or forms exactly four chemical bonds.

1859-1860: Gustav Kirchhoff and Robert Bunsen - Apply spectroscopy to chemical analysis, which lead them to the discovery of caesium and rubidium. Other workers soon used the same technique to discover indium, thalium, and helium.

1862: Alexandre-Emile Béguyer de Chancourtois - published the telluric helix, an early, three-dimmensional version of the Periodic Table of the Elements.

1863: John Newlands - Law of Octaves, an early version of the octet rule and precursor to the Periodic Law.

1864: Lothar Meyer - Early version of the periodic table, with 28 elements organized by valence.

1865: Johann Josef Loschmidt - determined exact number of molecules in a mole, later named Avogadro's Number.

1865: Friedrich August Kekulé von Stradonitz - Working on the work of Loschmidt and others, establishes structure of benzene as a six carbon ring with alternating single and double bonds.

1869: Dmitri Mendeleev - First modern periodic table, with all known elements organized by atomic weights, and as-yet-undiscovered elements correctly placed in their correct locations.

1873: Jacobus Henricus van 't Hoff - developed a model of chemical bonding that explained the chirality experiments of Pasteur and provided a physical cause for optical activity in chiral compounds.

1876: Josiah Willard Gibbs - Publishes On the Equilibrium of Heterogeneous Substances, a compilation of his work on thermodynamics and physical chemistry which lays out the concept of free energy to explain the physical basis of chemical equilibria.

1877: Ludwig Boltzmann - Establishes statistical derivations of many important physical and chemical concepts, including entropy, and distributions of molecular velocities in the gas phase.

1880: Adolf von Baeyer - Synthesis of indigo dye, a milestone in modern industrial organic chemistry which revolutionized the dye industry.

1883: Svante Arrhenius - Developed ion theory to explain conductivity in electrolytes.

1884: Jacobus Henricus van 't Hoff - Publishes Études de Dynamique chimique, the groundbreaking study on chemical kinetics.

1884-1894: Hermann Emil Fischer - Structure and synthesis of glucose and related sugars.

1885: Henry Louis Le Chatelier - Le Chatelier's principle explains the response of dynamic chemical equilibria to external stresses.

1886: Eugene Goldstein - Named the cathode ray, later discovered to be composed of electrons, and the canal ray, later discovered to be positive ions that had been stripped of their electrons in a cathode ray tube.

1891: Vladimir Shukhov - Develops first thermal cracking techniques important to petrochemical industry.

1893: Alfred Werner - Discovers the octahedral structure of cobalt complexes, thus creating the field of coordination chemistry.

1897: Joseph John Thomson - Discovery of the electron using the cathode ray tube.

1898: Wilhelm Wien - Demonstrates that canal rays (streams of positive ions) can be defelected by magnetic fields, and that the amount of deflection is proportional to the mass-to-charge ratio. This discovery would lead to the analytical technique known as mass spectrometry.

1898: Maria Skłodowska-Curie and Pierre Curie - isolation of radium and polonium from pitchblende.

c. 1900: Ernest Rutherford - Discovery of the source of radioactivity as decaying atoms; coins terms for various types of radiation.

1900: Mikhail Semyonovich Tsvet - Invents chromatography, an important analytic technique.


20th century

1902: Gilbert N. Lewis - devises Lewis dot diagrams to describe valence bonding in molecules.

1904: Hantaro Nagaoka - Proposes an early nuclear model of the atom, where electrons orbit a dense massive nucleus.

1904-1914: Frederick Soddy - Discovers that elements can have different isotopes.

1905: Fritz Haber and Carl Bosch - Develop the Haber process for making ammonia from its elements, a milestone in industrial chemistry with deep consequences in agriculture. [25]

1905: Albert Einstein - Explains Brownian motion in a way that definitively proves Atomic Theory.

1907: Leo Hendrik Baekeland - Invented bakelite, one of the first commercially successful plastics.

1909: Ernest Rutherford, Hans Geiger, and Ernest Marsden - Gold foil experiment proves the nuclear model of the atom, with a small, dense, positive nucleus surrounded by a diffuse electron cloud.

1909: Robert Millikan - Oil drop experiment confirms existence of electron as the quanta of electric charge, determines charge/mass ratio of an electron.

1909: S. P. L. Sørensen - Invents the pH concept and develops methods for measuring acidity.

1911: Antonius Van den Broek - Proposes idea that the elements on the periodic table are more properly organized by positive nuclear charge rather than atomic weight.

1912: William Henry Bragg and William Lawrence Bragg - Bragg's law establishes the field of X-ray crystallography, an important tool for elucidating the crystal structure of compounds.

1912: Peter Debye - Developed concept of molecular dipole to describe assymetric charge distribution in some molecules.

1913: Niels Bohr - Introduces concepts of quantum mechanics to atomic structure by proposing what is now known as the Bohr model of the atom, where electrons exist only in strictly defined orbitals.

1913: Henry Moseley - Introduces concept of atomic number to fix inadequacies of Mendeleev's periodic table based on atomic weight, experimentally proves Van den Broek's idea.

1913: Joseph John Thompson - Shows that charged subatomic particles can be seperated by their mass-to-charge ratio, a technique known as mass spectrometry.

1916: Gilbert N. Lewis and Irving Langmuir - Publish "The Atom and the Molecule", the foundation of valence bond theory.

1918: Arthur Jeffrey Dempster - Develops first practical modern mass spectrometer

1922: Otto Stern and Walther Gerlach - establish concept of quantum mechanical spin in subatomic particles.

1923: Gilbert N. Lewis and Merle Randall - Publish Thermodynamics and the Free Energy of Chemical Substances, first modern treatice on chemical thermodynamics.

1923: Gilbert N. Lewis - Develops electron pair theory of acid/base reactions.

1924: Louis de Broglie - Introduces the wave-model of atomic structure, based on the ideas of wave-particle duality.

1925: Wolfgang Pauli - Develops the exclusion principle, which states that no two electrons around a single nucleus may have the same quantum state, described by four quantum numbers.

1926: Erwin Schrödinger - The Schrödinger equation provides a mathematical basis for the wave model of atomic structure.

1926: Gilbert N. Lewis - coins term "photon" to describe the particle of light.

1927: Werner Heisenberg - Develops the uncertainty principle which, among other things, explains the mechanics of electron motion around the nucleus.

c. 1930: Linus Pauling - Pauling's rules form basic underpinning for the use of X-ray crystalography to deduce molecular structure.

1930: Wallace Carothers - Leads team of chemists at DuPont who invent nylon, one of the most comercially successful synthetic polymers in history.

1931: Erich Hückel - Hückel's rule explains when a planar ring molecule will have aromatic properties.

1931: Harold Urey - Discovers deuterium.

1932: James Chadwick - Discovers the neutron.

1932: Linus Pauling - first describes electronegativity as a means of predicting the dipole
moment of a chemical bond.

1935: Arthur Jeffrey Dempster - Discovers Uranium-235, an isotope vital to the development of the atomic bomb and of commercial nuclear power.

1937: Carlo Perrier and Emilio Segrè - First confirmed synthesis of technetium-97, the first artificially produced element, filling a gap in the periodic table. The element may have been synthesized as early as 1925 by Walter Noddack and others.

1937: Eugene Houdry - develops industrial scale catalytic cracking of petroleum for first modern oil refinery.

1938: Pyotr Kapitsa, John Allen and Don Misener - Produced supercooled helium-4, the first zero-viscosity superfluid, a substance that displays quantum mechanical properties on a macroscopic scale.

1939: Linus Pauling - Publishes The Nature of the Chemical Bond, a compilation of a decades worth of work on chemical bonding. It is one of the most important modern chemical texts. It explains hybridization theory, covalent bonding and ionic bonding as explained through electronegativity, and resonance as a means to explain, among other things, the structure of benzene.

1940: Edwin McMillan and Philip H. Abelson - Identification of neptunium, the lightest and first synthesized transuranium element, identified in the products of uranium fission.

1941: Glenn T. Seaborg - Takes over McMillan's work creating new atomic nuclei. Pioneers method of neutron capture and later through other nuclear reactions. Would become the principal or co-discoverer of nine new chemical elements, and dozens of new isotopes of existing elements.

1945: Jacob A. Marinsky, Lawrence E. Glendenin, and Charles D. Coryell - First confirmed synthesis of Promethium, filling in the last "gap" in the periodic table.

1945-1946: Felix Bloch and Edward Mills Purcell - Discovers the process of Nuclear Magnetic Resonance, an analytical technique important in elucidating structures of molecules, especially in organic chemistry.

c. 1950: Alan Walsh - Pioneered the field of atomic absorption spectroscopy, an important quantitative spectroscopy method that allows one to measure specific concentrations of a material in a mixture.

1951: Linus Pauling - Use of X-ray crystalography to deduce the secondary structure of proteins.

1952: Robert Burns Woodward, Geoffrey Wilkinson, and Ernst Otto Fischer - Discover the structure of ferrocene, leading to a boom in the field of organometallic chemistry.

1953: James D. Watson and Francis Crick - Propose the structure of DNA, opening the door to the field of molecular biology.

1958: Max Perutz and Sir John Cowdery Kendrew - First use of X-ray crystallography to elucidate a protein structure, specifically Sperm Whale myoglobin.

1962: Neil Bartlett - Synthesizes xenon hexafluoroplatinate, showing for the first time that the noble gases can form chemical compounds.

1965: Linus Pauling - Proposes the Close-Packed Spheron Model of the atomic nucleus as a means to explain the specific organization of the atomic nucleus.

1965: Robert Burns Woodward and Roald Hoffmann - Use the symmetry of molecular orbitals to explain the stereochemistry of chemical reactions (the Woodward-Hoffmann rules).

1966: Franklin H. Field and M. S. Burnaby Munson - Develop chemical ionization mass spectrometry, a soft ionization technique that reduced the amount of fragmentation observed during electron ionization.

1975-1976: Richard R. Ernst - Develops the technique of Fourier Transform NMR, greatly increasing the sensitivity of the technique, and opening the door for magnetic resonance imaging or MRI.

1985: Harold Kroto, Robert Curl and Richard Smalley - Discovery of fullerenes, a class of large carbon molecules superficially resembling the geodesic dome designed by architect R. Buckminster Fuller.

1991: Sumio Iijima - First practical production of a type of cylindrical fullerene known as a carbon nanotube, though earlier work had been done in the field as early as 1951.

1995: Eric Cornell and Carl Wieman - Produce the first Bose–Einstein condensate, a substance that displays quantum mechanical properties on the macroscopic scale.

Source : wikipedia