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Democritus
Proposed that matter was composed of tiny indivisible particles. -
John Dalton
Based his theory on experimental data, and said that the atom is a uniform or a solid sphere. He also said all atoms are made of elements, and that atoms of the same element have the same mass. Also that atoms of different elements have different masses. He goes on saying that compounds contain atoms of more than one element and that atoms of different elements always combine in the same way in a particular compound. -
Eugine Goldstine
Founder of positive charged atoms. He also discovered anode rays. -
J. J. Thomson
Positive spheres with negative electrons throughout the whole atom -
Hantaro Nagaoka
Devoloped an early planetary model of the atom. This was a major changing point in history. -
Ernest Rutherford
He said there is a dense, positive charge in the center of the atom called the nucleus, surrounded by negative electrons -
Niels Bohr
He said that electrons can only exist in specific energy states. He also says that the electrons move in circular orbits within the specific energy levels. -
Erwin Schrodinger
Invented the electron cloud model. He says that the electrons (e-) are most likely to be found in the orbital, which is the region around the nucleus. -
James Chadwick
Says that the neutral particles are in the nucleus of an atom. Chadwick based his theory on the Rutherfords Nuclear model and revised it. -
Nuclear Bomb
An explosive weapon that becomes a destructive force from the nuclear reactions by fission and fussion. Small amounts of matter releases amounts of energy. -
Sir Isaac Newton
Proved that a prism could decompose white light into a spectrum of colors. -
Isotopes
Share the same number of protons of an element. Also ech isotope has a certain amount of neutrons -
Aristotle
His work was a beginning step for other scientists and people.
