History of the Atom - Jake Tapia

  • Antoine Lavoiser

    Antoine Lavoiser
    Discovered that matter was conserved during chemical reactions.
  • Period: to

    History of the Atom

  • John Dalton

    John Dalton
    Proposed that atoms had a measurable mass. It supported Aristotle's theory of atoms.
  • Henri Becquerel

    Henri Becquerel
    While studying the effect of x-rays on photographic film, he discovered some chemicals spontaneously decompose and give off very pentrating rays.
  • J.J. Thomson

    J.J. Thomson
    Used a cathode ray tube to determine the electron's charge to mass ratio which is 1.759X10^8 coulombs/gram.
  • The Curies

    The Curies
    Discovered the elements polonium and thorium and also that certain elements were radioactive. The more radioactive, the shorter the half life.
  • Max Planck

    Max Planck
    Theory of quanta or that energy was released in little packets instead of one continuous stream.
  • Robert Millikan

    Robert Millikan
    Discovered the electron charge and mass with an oil drop experiment. Supporting J.J. Thomson's theory even more.
  • Rutherford

    Shot alpha particles at a thin gold film and realized that a few bounced back. Thus proposing the idea of a dense positively charged proton.
  • Niels Bohr

    Niels Bohr
    Made the Bohr model and disproved the previouse theory of an atom's composition by placing the atoms on the outside in different layers.
  • Mosley

    Used x-ray tubes to find the charge of an atom's nucleus. It was supported by Rutherford's theory of a positively charged nucleus.
  • Werner Heisenberg

    Werner Heisenberg
    Principle of Indeterminacy you can’t know the position and velocity of something at the same time.
  • Erwin Schrodinger

    Erwin Schrodinger
    Proposed the idea that electrons are outside of the atome in a "cloud" formation. Based on Bohr's theory of an atom.
  • James Chadwick

    James Chadwick
    Found that there were also particles with no charge in the nucleus called neutrons.