atomic history timeline by austin fernandez

  • 350


    Aristotle didnt think atoms could be constantly moving if they were in a void. He beleived there were four elements and four qualities, and that they would align into their rightful place and be at rest.
  • 442

    Thinking about matter BC

    Democritus, a Greek philosopher, co-originated the thought (with his teacher, Leucippus) that all matter is composed of indivisible elements.
  • isaac newton

    theorized a mechanical universe with small, solid masses in motion.
  • Antoine Lavoisier

    Lavoisier was a French nobleman that founded several elements and put the first table of elements together.
  • John dalton and atoms

    a British chemist and physicist, developed a theory that matter is simply composed of atoms of different weights and is combined in ratios by weight.
  • michael faraday

    Studied the effect of electricity on solutions, coined term "electrolysis" as a splitting of molecules with electricity, developed laws of electrolysis.
  • j.plucker

    Built one of the first gas discharge tubes ("cathode ray tube").
    The cathode ray tube (CRT) is a vacuum tube containing one or more electron guns, and a fluorescent screen used to view images.
  • dimtri mendeleev

    He discovered that the properties of elements "were periodic functions of the their atomic weights"
  • Early quantum theory developed

    Max Planck introduced what would be known as quantum theory, stating that electromagnetic energy could only be emitted in quantized form. His quanta are now called photons by physicists.
  • Neils Bohr

    This man suggested that electrons travel around the nucleus in definite paths. These paths are always at a certain "level" away from the nucleus.
  • Louis Victor de Broglie

    Electrons are similar to both particles and waves.
  • Heisenberg

    Described atoms by means of formula connected to the frequencies of spectral lines. Proposed Principle of Indeterminancy - you can not know both the position and velocity of a particle.
  • James Chadwick

    Jame Chadwick was an English scientist that discovered the neutron. Before this discovery, Rutherford had concluded that the nucleus was made of positive matter.
  • James Chadwick

    Using alpha particles discovered a neutral atomic particle with a mass close to a proton. Thus was discovered the neutron.
  • Nuclear fission developed

    Otto Hahn, regarded as the father of nuclear chemistry, discovers nuclear fission, along with Lise Meitner.