Atomic Theory Timeline

By bonhagcm
  • 350 BCE

    Democritus

    Theorized that matter was made of small, indivisible particles which he named atomos

  • Antoine Lavoisier

    The Law of Conservation of Mass

  • Joseph Proust

    The Law of Definite Proportions

  • John Dalton

    Created the Law of Multiple proportions, which led to the Atomic Theory

  • Dimitri Mendeleev

    Periodic law, and first draft of periodic table

  • J. J. Thomson

    Cathode ray experiments which led to discovery of electron

  • Ernest Rutherford

    Gold foil Experiment, which led to the Nuclear Theory

  • James Chadwick

    Discovered Neutrons

  • Neil Bohr

    Bohr model

  • Henry Moseley

    Atomic number