Atomic Structure

By nickraak
  • 460 BCE

    Democritus

    Democritus
    All matter made is made small particles with different properties.
  • 300 BCE

    Aristotle

    Aristotle
    All things made of either earth, fire, water, or air.

  • Antoine Lavoisier

    Antoine Lavoisier
    Created the Law of Conservation, stating mass cannot be lost or gained.

  • John Dalton

    John Dalton
    All matter is made of atom and all atoms that make up the element have same mass.

  • Amedeo Avogadro

    Amedeo Avogadro
    Equal volumes of different gases have the same number of molecules.

  • Jöns Jacob Berzelius

    Jöns Jacob Berzelius
    Made table of atomic weights of 43 elements. Discovered Silicon and Selenium.

  • Dmitri Mandeleev

    Dmitri Mandeleev
    Created first Periodic Table of the Elements.

  • J. J. Thomson

    J. J. Thomson
    Discovered electrons with cathode-ray tube, along with Plum Pudding Model stating that protons were inside nucleus of meterial like plum pudding with electrons surrounding.

  • Henry Moseley

    Henry Moseley
    Used X-Rays to study atomic structures and found that atomic number equals number of protons in the element.

  • Erwin Schrodinger

    Erwin Schrodinger
    Said that atom has an "electron cloud", when electrons were likely to be found, but not always in one spot, surrounding the nucleus.

  • James Chadwick

    James Chadwick
    Discovered the existence of the neutron in the atom.

  • Henri Becquerel

    Henri Becquerel
    Discovered radioactivity.

  • Marie Curie

    Marie Curie
    Discovered radium and polonium and made the word Radioactivity

  • Max Planck

    Max Planck
    Created the Quantum Theory by describing glowing matter using quanta.

  • Ernest Rutherford

    Ernest Rutherford
    Did Gold Foil Experiment, proving the existence of the nucleus of an atom. The forming the Rutherford Model.

  • Niels Bohr

    Niels Bohr
    Formed the Planetary Model, which stated that electrons orbit the nucleus like the moon orbits earth. Also that the Periodic Table can predict atomic structure.

  • Robert Millikan

    Robert Millikan
    Found the charge of the electron.

  • Werner Heisenberg

    Werner Heisenberg
    Created the principle of Indeterminacy, stating that position and velocity of a particle is unknown.

  • Lise Meitner

    Lise Meitner
    Discovered nuclear fission.