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Period: May 17, 1000 to
TIMESPAN
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Issac Newton
The date is unknown for all of them (I couldn't find them) so I just put a random date Proposed a mechanical universe with small solid masses in motion. -
John Dalton
Proposed an "atomic theory" with spherical solid atoms based upon measurable properties of mass. -
Michael Faraday
Studied the effect of electricity on solutions, coined term "electrolysis" as a splitting of molecules with electricity, developed laws of electrolysis. Faraday himself was not a proponent of atomism. -
J. Plucker
Built one of the first gas discharge tubes ("cathode ray tube"). -
Dimitri Mendeleev
Arranged elements into 7 groups with similar properties. He discovered that the properties of elements "were periodic functions of the their atomic weights". This became known as the Periodic Law. -
James Clerk Maxwell
Proposed electric and magnetic fields filled the void. -
Sir William Crookes
Discovered cathode rays had the following properties: travel in straight lines from the cathode; cause glass to fluoresce; impart a negative charge to objects they strike; are deflected by electric fields and magnets to suggest a negative charge; cause pinwheels in their path to spin indicating they have mass. -
E. Goldstein
Used a CRT to study "canal rays" which had electrical and magnetic properties opposite of an electron. -
GJ. Stoney
Proposed that electricity was made of discrete negative particles he called electrons -
Wilhelm Roetgen
Using a CRT he observed that nearby chemicals glowed. Further experiments found very penetrating rays coming from the CRT that were not deflected by a magnetic field. He named them "X-rays". -
Soddy
Observed spontaneous disintegration of radioactive elements into variants he called "isotopes" or totally new elements, discovered "half-life", made initial calculations on energy released during decay. -
Nagaoka
Postulated a "Saturnian" model of the atom with flat rings of electrons revolving around a positively charged particle. -
Ernest Rutherford
Using alpha particles as atomic bullets, probed the atoms in a piece of thin (0.00006 cm) gold foil . He established that the nucleus was: very dense,very small and positively charged. He also assumed that the electrons were located outside the nucleus. -
de Broglie
Discovered that electrons had a dual nature-similar to both particles and waves. Particle/wave duality. Supported Einstein. -
Schrodinger
Viewed electrons as continuous clouds and introduced "wave mechanics" as a mathematical model of the atom. -
Ernico Fermi
Conducted the first controlled chain reaction releasing energy from the atoms nucleus.