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12 Cards in this Set

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  • Back
German physicist who showed that the impact of the cathode ray with a material object created a new ray, which he dubbed the "X-ray"
Wilhelm Roentgen
English chemist who offered the experimental evidence for atoms based upon the laws of Conservation of Mass and Constant Composition.
John Dalton
German physicist who used discharge tubes to discover cathode-rays and canal-rays, which lead to the discovery of the proton.
Eugen Goldstein
English physicist who discovered the electron in 1897 and later determined the charge for the electron.
J.J. Thompson
American physicist who determined the charge of an electron by studying the motion of charged oil droplets in an electric field
Robert Millikan
English physicist who discovered evidence for an atomic nucleus by firing high-velocity alpha particles at a thin gold foil
Ernest Rutherford
English physicist who discovered the neutron after bombarding beryllium-9 with alpha particles and analyzing the radioactive emission.
James Chadwick
Austrian physicist that used complex mathematics to express the position and momentum of an electron as a wave of probability
Erwin Schrodinger
German scientist that developed the Uncertainty principle describing the impossibility of knowing an electron's position and momentum simultaneously.
Werner Heisenberg
German physicist who reasoned that if matter is made up of particles then light energy may also be composed of particles; he named a particle of light a quantum
Max Planck
Danish physicist who combined the quantum principle with the emission spectrum of hydrogen gas as evidence that electrons are found only in fixed energy levels.
Niels Bohr
Polish scientist, studying and teaching in France, which worked with radioactive materials and later discovered the elements Polonium and Radium
Marie Curie