Atomic Model Timeline

By wtam16
  • 400 BCE

    Democritus

    Democritus
    Democritus lived from about 460 BC - 370 BC. Around 400 BC, he speculated that the atom is the building block of all things. As well as the idea that they are tiny, uncuttable particles.
  • 395 BCE

    World Event: The Corinthian War Begins

    World Event: The Corinthian War Begins
    About 5 years after Democritus' discovery the Corinthian War begins between Athens, Thebes, Corinth, and Argos against Sparta.
  • World Event: Louisiana Purchase

    World Event: Louisiana Purchase
    The Lousiana Purchase occured the same year as Jack Daltons discovery
  • John Dalton: Marble Model

    John Dalton: Marble Model
    John Dalton (1766-1884) is considered "The Father of Modern Chemistry". He discovered that elements reacted in a whole-number ratio. He came up with the "marble" model, a simple sphere representing an atom.
  • Michael Faraday

    Michael Faraday
    Michael Faraday (1791-1867) introduced the idea that atoms could be interacted with through forces of electricity and magnetism.
  • Eugene Goldstein

    Eugene Goldstein
    Eugene Goldstein (1850-1930) discovered canal rays (positively charged particles) contributing to the understanding that atoms contain subatomic particles.
  • JJ Thomson: Plum Pudding Model

    JJ Thomson: Plum Pudding Model
    JJ Thomson (1856-1940) discovered the electron and proposed a "plum pudding" model in 1887 where electrons are embedded in a positively charged sphere.
  • World Event: The Eiffel Tower Opens

    World Event: The Eiffel Tower Opens
    The Eiffel Tower first opened in 1889, two years after the plum pudding model was introduced.
  • Robert Millikan

    Robert Millikan
    Robert Millikan (1868-1953) discovered that electrons all carry the same amount of a negative charge
  • Ernest Rutherford: Nuclear Model

    Ernest Rutherford: Nuclear Model
    Ernest Rutherford (1871-1937) Discovered the nucleus of an atom with his famous gold foil experiment. He created the "Nuclear model" with a dense positively charged core with electrons orbiting it.
  • Neils Bohr: Solar System Model

    Neils Bohr: Solar System Model
    Neils Bohr (1885-1962) proposed a model of the atom in which electrons orbit the nucleus of ana tom in a planetary-like mtion.
  • WWI Begins

    WWI Begins
    WWI begins just a year after Bohr's discovery
  • World History: Treaty of Versaille Signed

    World History: Treaty of Versaille Signed
    In 1919 the Treaty ofVersaille is signed, formally ending WWI
  • Edwin Shroedinger: Electron Cloud Model

    Edwin Shroedinger: Electron Cloud Model
    Edwin Shroedinger (1887-1961) proposed that electrons travel in waves in a designated space. Electrons = matter waves.
  • Werner Heisenburg

    Werner Heisenburg
    Werner Heisenberg (1901-1976) discovered there's a limit to the accuracy of the data collected when trying to determine the physical properties of an electron such as location speed/position momentum.
  • James Chadwick: Electron Cloud Model with Neutrons

    James Chadwick: Electron Cloud Model with Neutrons
    James Chadwick (1891-1974) discovered that there was another subatomic particle within the nucleus of an atom. This was the neutron, a subatomic particle void of charge.
  • World Event: The Start of WW2

    World Event: The Start of WW2
    About 7 years after Chadwicks discoveries, WW2 started when Germany declared war on Poland.