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Isaac Newton
Newton believed there were tiny particles everywhere that were constantly moving. -
Dalton
John Dalton theorized that all matter consists of tiny indestructible particles and that elements are characterized by math. -
Michael Faraday
Faraday said that the number of elements separated by by passing an electrical current through molten or dissolved salt is proportional to the charge of a circuit. -
J. Plucker
Plucker discovered the electric discharge of a cathode ray created a fluorescent glow on the walls of the tube. -
Dmitri Mendeleev
Mendeleev created the first version of the periodic table and used it to predict properties of elements that had not yet been discovered. -
James Maxwell
Created the electromagnetic theory. He made the connection between light and electromagnetism. -
G.J. Stoney
Proposed that electricity is made of negatively charged particles. -
Wilhelm Roentgen
Produced and detected electromagnetic radiation now known as as x-rays. -
JJ Thomson
Discovered the electron. Developed the plum pudding model. -
Marie Curie
Curie discovered the radioactive elements polonium. -
Max Planck
Proposed a theory that energy did not flow at a steady rate but was instead delivered in packets called quanta. -
Frederick Soddy
Explained that radioactivity is caused by the transmutation of elements. In 1913 he also concluded that elements can exist in different forms called isotopes. -
Phillip Lenard
Discovered that cathode rays can not exist outside of discharge tubes. Used an experiment in which a thin aluminum slide was was put on the end of a cathode ray tube. The experiment showed that as the slide was pulled away the ray decreased and eventually vanished completely. -
Hantaro Nagaoka
Disagreed with Thomsons model. Believed electrons orbited outside of the atom and could not be found in a positively charged atom. He developed the Saturn Model. -
Albert Einstein
Einstein created the theory of relativity and also created the law of mass-energu equivelance E=mc^2. -
Hans Geiger
Developed the Geiger counter which is an electronic tool for measuring radioactivity. -
R.A. Millikan
Millikan proposed that the charge of water is a multiple of the elementary electrical charge. -
Ernest Rutherford
Using the gold foil experiment he discovered the positively charged nucleus. He also found that atoms were mostly empty space and that electrons were found in this space. -
Niels Bohr
Discovered that electrons travel in orbits around the nucleus. Said that the number of electrons determine an elements properties. -
H.G.J. Moseley
Using experiments on x-ray spectra he discovered that the atomic number of an element is equal to the number of protons in it. -
Louis de Broglie
Discovered the wave nature of electrons -
Erwin Schrodinger
Suggested electrons were arranged into orbitals which were systematically distributed throughout the electron cloud. He also defined an orbital as a region in which an electron could be found. -
Werner Heisenburg
Found a way to formulate quantum physics. He proposed the uncertainty principle. -
Paul Dirac
Predicted the existence of antiparticles -
James Chadwick
Discovered the neutron and helped to develop the atomic bomb. He used nuclear fission in his experiments. -
John Douglas
Disintegrated Lithium atoms through the bombardment of photons. -
Ernest Lawrence
Lawrence invented the first particle accelerator to achieve high energy levels. -
Lisa Meitner
Discovered Barium after bombarding uranium with neutrons. -
Glenn Seaburg
Discovered the transuranium elements. -
Enrico Fermi
Fermi conducted the first controlled chain reaction and also helped to develop the first nuclear reactor.
