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410
Aristotle's theory
Aristotle thought that the world was made up of 4 main elements, fire, water, air and, earth. There were also four qualities hot, cold, dry and wet. Fire was hot and dry, water was cold and wet. -
410
Democritus's Theory
This Greek philosopher hypothesized that if you take a rock and break this rock into a powder and then breaking down the powder until the powdered rock is turned into tiny bits of matter that cannot be broken down any further. Thus creathing the atomic theory of matter that will soon be researched more throught time. -
Period: 410 to
Developing the Atomic Theory
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Isaac Newton's Theory
Sir Isaac Newton theorized that everything is made up of tiny masses of particals that move. -
Robert Boyle's Theory
Robert Boyle's contrbution to the atomic theory is that he hepled develop a defenation of and element and helped with the "death" of the four elements. -
Joseph Priestly
Joseph Priestly's biggest contrbution to the atomic theory is the discovey of the gas that is named oxygen (which he called dephlogisticated air). -
Anotoine Lavoisier's Theory
Antoine Lavoisier named oxygen after visiting Joseph Priestly and hydrogen. -
John Dalton's Theory
John Dalton reconsidered the ancient idea that a different element is made up of a different atom. Dalton thought that atoms varied in size shape and colour using the following theory that
-all matter is made up of same particals called atoms
-all atoms of the same element are identical in properties
-atoms of different elements have different properties
-atoms of different elements can combine to make a new substance -
J.J. Thomson's Theory
J.J. Thomson researched that atoms might be maddde up of other particals. Thomson experimented using a cathode ray tube. Using the tube he the discoverd electrons. -
James Chadwick's Theory
James Chadwick (Rutherford's student) refined the concept of the nucleus and found that the nuleus is made up of neutral particals and positively charged particals called neutrons and protons. -
Ernest Rutherford"s Theory
Rutherford tested further tested Thomson's theory by shooting positive particals into a hole in a lead block which then was directed at a thin sheet of pure gold. In the experiment about 1 in 10 000 particals bounced off the sheet where Rutherford discoverd the nucleus in an atom.
