Atomic Timeline

  • Plato
    427 BCE

    Plato

    said that atoms are ideal geometric forms
  • Democritus
    400 BCE

    Democritus

    Believed atoms were uniformed. Central figure in the atomic theory.
  • The Alchemists
    500

    The Alchemists

    The Alchemists believed all metals were formed from 2 principals. These consist of mercury and sulfur.
  • Solar System Model

    Solar System Model

    Neils Bohr created the Solar System Model
  • Robert Boyle

    Robert Boyle

    Believed everything was made of tiny particles
  • Antone Lavoisier

    Antone Lavoisier

    he explained that matter is conserved during chemical changes
  • Billiard Ball Model

    Billiard Ball Model

    John Dalton created the Billiard Ball Model
  • John Dalton

    John Dalton

    said that all matter is made of invisible atoms
  • Amedeo Avogadro

    Amedeo Avogadro

    stated that all atoms are reletively the same size
  • Dmitri Mendeleev

    Dmitri Mendeleev

    put elements in order (periodic table)
  • JJ Thompson

    JJ Thompson

    JJ Thompson discovered the electron
  • Pierre and Marie Curie

    Pierre and Marie Curie

    discovered polonium and radium
  • Ernest Rutherford

    Ernest Rutherford

    Discovered that there were 2 types of radiations
  • Plum Pudding Model

    Plum Pudding Model

    JJ Thompson created the Plum Pudding Model
  • Robert Millikan

    Robert Millikan

    discovered the elementary charge of an electron through experiment.
  • Neils Bohr

    Neils Bohr

    Said "some physical quantities only take discrete values"
  • Henry G.J. Moseley

    Henry G.J. Moseley

    Discovered the Moseley law -xray-
  • Albert Einstein

    Albert Einstein

    Mathematically proved atoms are real. He also proved liquids are made of molecules.
  • Electron Cloud Model

    Electron Cloud Model

    Eruin Schordinger created the Electron Cloud Model
  • James Chadwich

    James Chadwich

    James Chadwich discovered neutrons