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Democritus believed that The universe is composed of two elements: the atoms and the void.
the atomic theory stated that
1.all matter consist of invisible paticles known as atoms
2.atoms are indivisible
3.atoms are indestructable -
Newton created a concept that the mechanical universe, due to the laws of motion is made up of small solid masses in motion aka atoms.
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dalton created the first atomic model which looked like one spherical mass. Daltons atomic theory consisted of four major ideas
1 all elements are composed of atoms
2 atoms are only similar to that of their own element
3 atoms of diffrent elements can phisically and chemically combine into whole number ratios
4 chemical reactions occur when atoms are seperated joined or rearranged. -
through Williams experiment he had found that cathode rays are negatively charged.
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Stoney created the concept that atoms contain even smaller particles that have a charge. he also pointed out that atoms give off an electric charge thus concieving the thought of electrons.
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penetrating rays coming from the CRT that were not deflected by a magnetic field. He named them "X-rays"
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J.J Thomson, while using a electric feild to diflect the beams in a cathode ray discovered that their must be a negative charge in the ray therfore confirming electrons within the atoms of the ray. also presents his plum pudding atomic model.
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planck came up with the thoery that atoms do not behave in the way we precieve this theory is known as quantum theory that do not follow regular human scaled physics so well.
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proposes a model depicting rings of electrons revolving around a positively charged particle. although it was wrong it opened a new thought of revolving electrons
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E=mc squared was einsteins trademark equation stating that energy equals mass times the velocity of light squared. later on einstein helped the allies win WW2 through his assistance in the manhattan prodject.
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during his goldfoil experiment he found that an atom has a small positively charged nucleus, also the atom was mostly empty space depicting the electrons orbiting the nucleus in a random fashinon.
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Used x-ray tubes, determined the charges of an atoms nucleus. He wrote The atomic number of an element is equal to the number of protons in the nucleus. This work was used to reorganize the periodic table based upon atomic number instead of atomic mass.
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Developed an explanation of atomic structure that shows electrons do not randomly move around in the atom in a random way this was known as the electrons orbital.
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Viewed electrons as continuous clouds and introduced "wave mechanics" as a mathematical model of the atom.
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this is the most upto date model of an atom to date this depicts the orbitals of electrons around a nucleus and gives us a better understanding of an atom it also shows diffrent energy levels and clouds where electrons are most likely found.
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Using alpha particles, he discovered a neutral particle with a mass close to that of a proton this is now known as a neutron.
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large elements capture neutrons and then become unstable causing a chain reaction that gives off neutrons thus causing the reaction to continue.
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the first atomic bomb is dropped on japan killing hundreds of thousands jappanese the next day anotherone wasused on nagasaki thus ending the war.
