Atom Timeline

  • 400 BCE

    Democritus

    Democritus
    Created the theory of atoms existence
  • Dalton

    Dalton
    Confirmed everything is created by atoms
  • Mendeleev

    Mendeleev
    Created the periodic table
  • Goldstein

    Goldstein
    Discovered positive particles in atoms
  • Thomson

    Thomson
    Discovered the electron
  • Rutherford

    Rutherford
    Discovered the common model of an atom
  • Millikan

    Millikan
    Discovered how to determine the charge of electrons
  • Bohr

    Bohr
    Discovered that electrons orbited nuclei in atoms
  • Planck

    Planck
    Created the quantum theory
  • Heisenberg

    Heisenberg
    Created the Uncertainty Principle:
    -You can never know the exact location of an electron
    -You can never know the exact amount of energy it produces
  • Chadwick

    Chadwick
    Discovered neutrons in an atom
  • Schrodinger

    Schrodinger
    Created an equation for tracking electron movements