Atomic Timeline

  • 460 BCE

    Democritus

    Democritus was a central figure in the development of the atomic theory of the universe.
  • 428 BCE

    Plato

    Plato founded the Academy, an academic program which many consider to be the first Western university.
  • 500

    The Alchemists

    The Alchemists made all sorts of materials for commerce, including medicines, pigments, metallic alloys, perfumes and cosmetics.
  • Robert Boyle

    Robert Boyle discovered that the volume of a gas decreases with increasing pressure and vice versa
  • Antone Lavoisier

    Antone Lavoiser established the law of conservation of mass, determined that combustion and respiration are caused by chemical reactions with what he named “oxygen,” and helped systematize chemical nomenclature, among many other accomplishments.
  • Amedeo Avogadro

    Amedeo Avogadro correctly hypothesized that equal volumes of gases, at the same temperature and pressure, contain equal numbers of molecules.
  • John Dalton

    John Dalton was an English chemist, physicist, and meteorologist, best known for introducing the atomic theory into chemistry and for his work on human optics.
  • Neils Bohr

    Niels Bohr proposed a model of the atom in which the electron was able to occupy only certain orbits around the nucleus.
  • Dmitri Mendeleev

    Dmitri Mendeleev devised the periodic classification of the chemical elements
  • JJ Tompson

    JJ Tompson helped revolutionize the knowledge of atomic structure by his discovery of the electron
  • The Curies

    The Curies scientific teamwork led to the discovery of radioactivity and two new elements in the periodic table
  • Albert Einstein

    Einstein's researches are, of course, well chronicled and his more important works include Special Theory of Relativity
  • Robert Millikan

    In 1910 Robert Millikan succeeded in precisely determining the magnitude of the electron's charge.
  • Ernest Rutherford

    Ernest Rutherford was responsible for a remarkable series of discoveries in the fields of radioactivity and nuclear physics.
  • Henry G. J. Mosely

    Henry Moseley carried out a systematic series of experiments which showed that the frequencies of the X-rays emitted from an elemental target
  • Werner Heisenberg

    Werner Heisenberg's theory resulted especially in the discovery of allotropic forms of hydrogen
  • Erwin Schrodinger

    in 1926 Erwin Schrodinger formulated a wave equation that accurately calculated the energy levels of electrons in atoms.
  • James Chadwich

    James Chadwich is best known for his discovery of the neutron in 1932.