Atomic Timeline

  • The Alchemists
    500 BCE

    The Alchemists

    The alchemists created a scientific process which turned into atomic theory. They have credit for discovering the atom
  • Plato
    427 BCE

    Plato

    Plato created atomic theory. The theory that everything is made up of one of five solid shapes.
  • Democritus
    400 BCE

    Democritus

    Democritus was the first person to come up with the idea that all matter is made of atoms
  • Robert Boyle

    Robert Boyle

    Robert Boyle created Boyles law. The law is the idea that decreasing volume will increase speed and pressure.
  • Antone Lavoisier

    Antone Lavoisier

    Antone Lavoisier discovered that Oxygen was a key component in combustion.
  • Billiard Ball Model

    Billiard Ball Model

    An atomic model proposed by Dalton. Dalton imagined atoms to be solid and spherical so he represented them with billiard balls.
  • John Dalton

    John Dalton

    Dalton made the theory that atoms were solid spheres and that the came together to build things. (the billiard ball model)
  • Amedeo Avogadro

    Amedeo Avogadro

    Avogadro was the first person to discover atoms could be in the form of molecules. He also discovered that equal volume regardless of the gas would have an equal number of molecules.
  • Dimitri Mendeleev

    Dimitri Mendeleev

    Mendeleev was the first person to design the periodic table of elements.
  • JJ Thompson

    JJ Thompson

    Thompson discovered electrons and proved that cathode rays had negatively charged particles. (Plum Pudding model)
  • Marie and Pierre Curie

    Marie and Pierre Curie

    The Curies worked together and discovered two new atoms, radium and polonium.
  • Plum Pudding Model

    Plum Pudding Model

    An atomic model proposed by J.J. Thomson. The model showed negatively charged atoms placed into a positively charged "dough".
  • Albert Einstein

    Albert Einstein

    Einstein confirmed atomic theory by proving it mathematically.
  • Robert Millikan

    Robert Millikan

    Millikan discovered the charge and mass of electrons by using an oil drop.
  • Ernest Rutherford

    Ernest Rutherford

    Rutherford created the idea that an atom has a positively charged nucleus with electrons floating around it.
  • Solar System Model

    Solar System Model

    An atomic model proposed by Bohr. The model shows a nucleus with electrons orbiting it, similar to our solar system.
  • Neils Bohr

    Neils Bohr

    Bohr discovered that electrons float around in a spherical orbit around the nucleus of an atom. (Solar system model)
  • Henry G.J. Mosely

    Henry G.J. Mosely

    Mosely discovered atomic numbers by using X-rays. Atomic numbers were added to the periodic table.
  • Werner Heisenberg

    Werner Heisenberg

    Heisenberg made the theory of quantum mechanics and his uncertainty principle.
  • Electron Cloud Model

    Electron Cloud Model

    An atomic model proposed by Erwin Schrodinger. This model showed a nucleus with many electrons orbiting in various levels that made it look like a cloud.
  • Erwin Schrodinger

    Erwin Schrodinger

    Schrodinger made a more advanced model of the atom by using mathematical equations. This model is known as the Electron Cloud model.
  • James Chadwich

    James Chadwich

    Chadwich discovered neutrons by using alpha particles. He named them neutrons because they had no charge.