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Democritus
Democritus was a Greek philosopher who was the first to discover atoms existed. He proposed atoms were indestructible and were in all forms of matter. He also suggested all atoms have different compositions. -
John Dalton
Dalton was a chemist from England. Using some of Democritus's work, Dalton discovered atomic structure. He proposed atoms of the same element are identical and that atoms cannot be destroyed nor created. -
Goldstein
Goldstein discovered protons with the cathode ray. It fluoresces light which showed positively charged protons. -
J.J. Thomson
J.J. Thomson was from England. J.J. Thomson found there were subatomic particles smaller than an atom. He first introduced that electrons were smaller than atoms. He used the cathode ray to find negatively charged particles. -
Ernest Rutherford
Rutherford was a physicist from New Zealand and a student of Thomson. In 1911, he overturned Thomson's work by discovering a positively charged nucleus. He proposed atoms were mostly empty space by performing the gold-foil experiment. the gold-foil experiment shot particles at gold foil making them go in different directions. -
Niels Bohr
Niels Bohr is Danish. He proposed electrons don't "randomly" orbit the nucleus. electrons orbit on energy levels. The first level can only take 2. The second can take 8; the third takes 18, and the fourth takes 32. -
Erwin Schrodinger
He focused on Hydrogen. He made mechanical models. "In 1926 Erwin Schrödinger formulated a wave equation that accurately calculated the energy levels of electrons in atoms." -
Chadwick
Chadwick discovered neutrons are in the nucleus too along with protons. Neutrons have no charge. -
Louis De Broglie
He specialized in mechanical chemistry. this is using mechanics in chemistry. He focused on how subatomic particles moved. Protons and neutrons vibrate in place, and electrons orbit the nucleus.