The Atomic Theory

  • Period: 460 BCE to 370 BCE

    Democritus

    Hypothesized that atoms can't be destroyed; they differ in size, shape, mass, position, and arrangement
  • 422 BCE

    Democritus' atomic model

    A round sphere with no electrons, protons, or neutrons. His contribution helped people understand the idea of an atom and helped other scientists dive deeper into the science of the atom and it's characteristics.
  • Period: 384 BCE to 322 BCE

    Aristotle

    Aristotle did not believe in the atomic theory but he taught so otherwise. He believed all materials on earth were made of the four elements, earth, fire, water, and air.
  • Period: to

    J.J. Thomson

    Born in Cheetham Hill and went to college to study mathematics and physics.
  • J.J. Thomson

    Created the "Plum Pudding Model" where each atom is a sphere pilled with a positively charged fluid which is known as the "pudding". Throughout this fluid there are negatively charged electrons, known as the "plums". Suggested that the positive fluid held negatively charged electrons.