atomic timeline

  • 1804 BCE

    The Alchemists

    The Alchemists
    They believed the atom was formed from the principles of Mercury & Sulfur.
  • 430 BCE

    Plato

    Plato
    He helped create the atomic model, which is atoms are geometric forms that break into triangles. Interestingly Plato would later teach Aristotle.
  • 400 BCE

    Democritus

    Democritus
    He helped create the very FIRST atomic model, and was an important discoverer in developing the Atomic Theory.
  • Robert Boyle

    Robert Boyle
    Robert Boyle was an Alchemist. He discovered gas volume decreases with increased pressure.
  • Antone Lavoisier

    Antone Lavoisier
    He helped found todays modern day chemistry. He helped discover that matter is made up of atoms, "Law of Conservation of Mass."
  • Billiard Bar Model

    Billiard Bar Model
    This model showed how an atom looks - specifically in a sphere. It was created by John Dalton.
  • John Dalton

    John Dalton
    He discovered Daltons Law - An ideal gas law only for real gases. He also helped create a model for atomic interactions.
  • Amedeo Avogadro

    Amedeo Avogadro
    Amedeo helped with the atomic theory, through discovering how many gases are not just composed of 1 atom, but 2. Avogadro was the very first scientist to discover elements in molecule form.
  • Dmitri Mendeleev

    Dmitri Mendeleev
    Dmitri Mendeleev created the periodic table of elements. This helped arrange all the chemical elements. Interestingly Mendeleev was Russian.
  • JJ Thompson

    JJ Thompson
    He discovered the electron in 1897. From this the structure of the atom was proposed. Interestingly Thompson married one of his students.
  • Pierre and Marie Curie

    Pierre and Marie Curie
    These scientists helped come up with the idea that certain radioactive particles cause atoms to break down and release radiation. This helped show us more ways of how atoms work. Interestingly they both share a Nobel Prize.
  • Plum Pudding Model

    Plum Pudding Model
    This shows how atoms can have a negative charge. This model was created by J.J. Thomson's.
  • Robert Millikan

    Robert Millikan
    He discovered the elementary charge of an electron.
  • Ernest Rutherford

    Ernest Rutherford
    He shut down the idea that all atoms were indestructible. He also discovered atoms nucleus and protons. Interestingly he has the element Rutherfordium named in his behalf.
  • Neils Bohr

    Neils Bohr
    He was one of the main creators who helped propose the model of the atom.
  • Solar System Model

    Solar System Model
    This represents Atoms like a solar system; the center is a nucleus (like a sun), while electrons orbit around the nucleus (like planets). This model was introduced by Neils Bohr.
  • Henry G. J. Mosely

    Henry G. J. Mosely
    He helped with the discovery of the Moseley periodic table. Interestingly Mosely was in the army during World War 1.
  • Albert Einstein

    Albert Einstein
    He discovered the mathematical atom. He helped prove the true existence of atoms, using a simple microscope.
  • Electron Cloud Model

    Electron Cloud Model
    The Electron Cloud Model is helpful to see the patterns and behaviors of electrons. It was created by Erwin Schrödinger and Werner Heisenberg.
  • James Chadwich

    James Chadwich
    James Chadwich importance stems from the fact that he was the discover of the neutron. Chadwich received a Nobel Prize.