Modern Atom Theory

By savytho
  • Isaac Newton

    He proposed a mechanical universe with small solid masses in motion.
  • John Dalton

    He proposed an "Atomic Theory" with spherical solid atoms based upon measurable properties of mass.
  • Michael Faraday

    He studied the effect of electricity on solutions as a splitting of molecules with electricity, and developed laws of electrolysis.
  • J Plucker

    He built the first gas discharge tubes.
  • Lothar Meyer

    Classified elements into six families by their valence
  • Dmitri Mendeleey

    He arranged elements into 7 groups with similar properties. He created the Periodic Law
  • James Clerk Maxwell

    Proposed electric and magnetic fields filled the void.
  • Sir William Crookes

    He discovered cathode rays has certain properties.
  • E. Goldstein

    Used a CRT to study canal rays which had electrical and magnetic properties opposite of an electron
  • J.J. Thomson

    Used a CRT to experimentally determine the charge to mass ratio of an electron and studied canal rays and found they were associated with the proton H+
  • G.J. Stoney

    Proposed that electricity was made of discrete negative particles he called electrons.
  • WIlhelm Roentgen

    Using a CRT he observed that nearby chemicals glowed. He made them X-rays
  • Henri Becquerel

    He discovered some chemicals spontaneously decompose and give off very penetrating rays.
  • Rutherford

    Studied radiations emitted from uranium and named them alpha and beta.
  • Soddy

    Observed spontaneous disintegration of radioactive elements into variants he called isotopes
  • Nagaoka

    Postulated a model of the atom with flat rings of electrons revolving around a positively charged particle
  • Abegg

    Discovered that inert gases had a stable electron configuration which lead to their chemical inactivity
  • Albert Einstein

    Published the famous equation E=mc 2
  • Hnas Geiger

    Developed an electrical device to click when hit with alpha particles
  • R.A. Millikan

    Oil drop experiment determined the charge and the mass of an electron
  • Ernest Rutherford

    Used alpha particles as atomic bullets, probed the atoms in a piece of thin gold foil
  • H.G.J. Moseley

    Using x-ray tubes, determined the charges on the nuclei of most atoms
  • Aston

    Discovered the existence of isotopes through the use of a mass spectrograph