History of Atomic Theory

  • Leucippus and Democritus Theory

    They came up with the idea that matter is composed of tiny particles. This brought up the atom.
  • Antoine Lavoiser

    He came up with Law of Conservation of Mass. Which states even if matter changes forms its mass stays the same. It more explained atoms.
  • John Dalton

    He discovered that elements existed even as packets of matter. This told you were atoms existed.
  • Discharge Tubes

    Scientist started proving what stuff was made of using discharge tubes. This help discover protons and electrons.
  • Oregon Gonstein

    He proved that matter must have a positive charge also. This changed the way people observed atoms.
  • J.J. Thompson

    He measured how much heat the cathodes generated. He was able to estimate the mass of the rays. He discovered the electrons.
  • Earnest Rutherford

    He did an experiment using an extremely thin piece of gold foil and a screen coated with zinc. He called the center of the atom the nucleus. He discovered Protons and Protons make up the atom's nucleus.
  • Niels Bohr

    He came up with the Bohr model. Which helps us determine how many atoms an elements has.
  • Werner Heisenburg

    He discovered that it is impossible to know with most certainty the momentum of an atom and its position.
  • Quantum Theory

    Heisenberg and other scientist created this theory that stated that electrons weren't particles or waves that they had properties of both and neither.