Atoms

By cwidje
  • 370

    Democritus

    Thought that everything was composed of small particles called atoms. 1
  • Isaac Newton

    Used experimental methods to turn Democritus's ideas into a scientific theory.
  • John Dalton

  • Dmitri Mendeleev

    Used atomic weight to organize the first periodic table.
  • J.J. Thompson

    Proved the existence of negative electrons via a cathode ray tube.
  • Ernest Rutherford

    Used a "gold-foil experiment" to prove that the nucleus was positive and that the electrons orbited it.
  • Max Planck

    Vibrated atoms to shwo measureable energy (quanta).
  • Niels Bohr

    Proved that electrons orbit at energy levels.
  • Albert Einstein

    Created formula for atomic power. e=mc^2
  • Robert Millikan

    Used "oildrop" experiment to prove mass of electron=1/2000 of proton. Charge of electron=-1 Charge of proton=+1
  • Erwin Schrödinger

    Electrons have erratic orbits.
    Electron cloud model.
  • James Chadwick

    Proved the existence of the neutron.