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Atomic Structure Timeline

By brimason123

  • Democritus

    Democritus
    460 BC- 370 BC
    1st Atomic Theory. Pre-Socratic philosopher who formulated an atomic theory for the cosmos.

  • Issac Newton

    Issac Newton
    Proposed a mechanical universe with small solid masses in motion.

  • John Dalton

    John Dalton
    Proposed an "atomic theory" with spherical solid atoms based upon measureable properties of mass.

  • Robert Brown

    Robert Brown
    Brownian Motion- Jittery motion of tiny observable particles

  • Michael Faraday

    Michael Faraday
    Used the term "electrolysis" as splitting an atom with electricity

  • James Joule

    James Joule
    Production of heat by volcanic electricity

  • Sir William Crookes

    Sir William Crookes
    Discovered cathode rays

  • JJ Thomson

    JJ Thomson
    Studied "canal rays" and found they were associated with the proton H+

  • The Curies

    The Curies
    Creation of a theory of radioactivity

  • Abegg

    Abegg
    Discovered that inert gases have a stable electron configuration

  • Albert Einstein

    Albert Einstein
    Published the famous equation E=MC^2

  • Hans Geiger

    Hans Geiger
    Made a device that detects alpha radiation particles.

  • Millikan

    Millikan
    Measured the charge of the electron and the photoelectric effect

  • Ernest Rutherford

    Ernest Rutherford
    Used alpha particles as atomic bullets.

  • Henry Moseley

    Henry Moseley
    Wrote, "The atomic number of an element is equal to the number of protons in the nucleus."

  • Aston

    Aston
    Discovered the existence of isotopes through the use of a mass spectrograph.

  • Niels Bohr

    Niels Bohr
    Developed an explanation of atomic structure.

  • Werner Heisenberg

    Werner Heisenberg
    Described atoms by means of formula connecyed to the frequencies of spectral lines.

  • Cockroft/ Walton

    Cockroft/ Walton
    Built an early linear accelerator and bombarded lithium with protons to produce alpha particles.

  • Schrodinger

    Schrodinger
    Introduced "wave mechanics" as a mathematical model of the atom.

  • Paul Dirac

    Paul Dirac
    Proposed anti-particles

  • James Chadwick

    James Chadwick
    Used alpha particles to discover a neutral atomic particle with a mass close to a proton.

  • Lise Meitner, Hahn, Strassman

    Lise Meitner, Hahn, Strassman
    conducted experiments verifying that heavy elements capture neutrons and form unstable products which undergo fission.

  • Glenn Seaborg

    Glenn Seaborg
    Suggested a change in the layout of the periodic table.

  • Enrico Fermi

    Enrico Fermi
    Conducted the first controlled chain reaction releasing energy from the atoms nucleus,