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Aug 25, 1000
Democritus (460-370 BC)
He was the first to suggest that matter could not be imfinitely divided. He have the name Atomos to describe the tiny particles that make up matter and move through empty spaces. "Atoms can not be created,destroyed,or further divided." He could not figure out what holds atoms together. -
Aug 25, 1000
Aristotle (384-322 BC)
He disagreed with democritus ideas that atoms moved through empty spaces. He did not believe in atoms because of personal ideas of nature. -
John Dalton's (1766-1844)
He was an english school teacher who marked the begining of the develpoment of atomic theroy. He used Democritus ideas about matter and revised them based on his own research. He explained the conversion of mass. -
Physicist J.J. Thompson (1856-1940)
He designed a series of experiments at Cambridge to determine the ratio of the particles charged to it's mass.His results stated that the mass of the particle was much less than that of the hydrogen atom,which went aghainst Dalton's therory that atoms were invisible. -
Earnest Rutherford (1871-1937)
He studied how positivley charged a-particles interacted with solid matter. He designed an experiment to see if a-particles would be deflected as they passed through a thin sheet of gold foil. Through his research he came to the conclusion that thomson's plum pudding model of the atom was incorrect. -
Robert Millikan (1868-1953)
He was an american physicist who designed an oil drop apparatus to determine the charge of the electron. He discovered that the charge was equal to a single unit of a negative charge. therefore the electron carries a charge of negative 1. -
James Chadwick (1891 - 1974)
Chadwick was an Eglish Physicist that demonstrated that the nucleus had another neutral subatomic particle, the neuton. Chadwick won the nobel prize for his discovery of the neutron.
