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Democritus' Discovery
Democruitis was as Greek philosopher that presented the idea that matter was created by smaller pieces that could not be separated into smaller parts. The importance of this discovery was that he realized that the atom is the smallest particle that can still be considered an element. -
Dalton's Discovery
Dalton had many experiments when it finally came to him, that Atoms of a given element are identical in size, mass, and other properties. He also said that atoms of different elements differ in size, mass, and that atoms cannot be created or destroyed. -
Mendeleev's Discovery
Dmitri Mendeleev discovered an impressive organization in chemistry with the focus of chemical elements that were necessary to create the Periodic Table of Elements. He recognized the relationship between atomic mass and other element properties needed for his spectacular organization. -
Rutherford's Discovery
Rutherford and his team, while experimenting, thought that the charged particles would travel right through the foil when aimed at it, also, that some of the paths of the different particles would deflect in some directions. While they did this experiment, their predictions came true because all of these things happened. This also lead him to believe that there was a part in the atom (nucleus) that packed the positive charge in it. -
Thomson's Discovery
Many scientists knew that there was no way that atoms could have any kind of an electrical charge but J.J. Thomas found a way to prove them wrong. Thomas found that atoms have opposing electrical charge particles. Since the scientists said the reverse of the charge in the atoms, he concluded that atoms would have to also contain some variety of a positive charge. -
Bohr's Discovery
Niels Bohr contributed to the revision of the atomic model by saying that electrons are only in specific orbits around the nucleus. This was compared to the planets orbiting the sun, and suggested that each orbit had a fixed energy. -
Chadwick's Discovery
James Chadwick was very important in scientific history because he discovered the Nucleus. Also, he was important because he discovered that neutrons were particles without a charge (not negative or positive--neutral).
