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Democritus was a famous greek philosipher and scientist. He believed that all matter cis made up of extremely small particles. he called these things Atoms.
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Dalton had made a theory that atomas were just solid spheres in which they come to gether to build things. He tried thid by using wooden spheres and sticks, connecting them together.
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He proposed the Combustion Theory which was based on sound mass measurements.
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Proposed the the Law of Constant Composition in 1799.
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Proposed what is now known as Avogadro's Hypothesis in 1811. The hypothesis states that at the same temperature and pressure, equal volumes of gases contain the same number of molecules or atoms.
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Mendeleyev had came up with the first design or drawing of the Periodical Table of Element.s
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Max was a German physicist. He is the founder of the Quantum Theory. The quantum theory focuses on the naturee of matter,(atoms.)
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Ernst had come to the conclusion that an atom has a dense positively chrged nucleus with the electrons floating randomly around the nucleus itself.
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Discovered cathode rays had the following properties: travel in straight lines from the cathode; cause glass to fluoresce; impart a negative charge to objects they strike; are deflected by electric fields and magnets to suggest a negative charge; cause pinwheels in their path to spin indicating they have mass.
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Niel had worked with Rutherford for a while but discovered that the electrons in an atom move in spherical orbits around the nucleus.
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Erwin had developed mathematical equations that describes the motion of an atom. He recieved the Nobel Prize for his work. His work also leads to an electron cloud model.
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James had confirmed that an atom had electrons but they are not charged.
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Broglie was a French physicist. Broglie had said that moving particles in an atom like electrons Have some properties of waves.
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Published his revolutionary equation showing that matter and energy were equivalent and interconvertible.
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Determined the unit charge of the electron in 1909 with his oil drop experiment at the University of Chicago. Which allowed for the calculation of the mass of the electron and the positively charged atoms.
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Discovered that the energy of x-rays emitted by the elements increased in a linear fashion with each successive element in the periodic table. In 1913, he proposed that the relationship was a function of the positive charge on the nucleus. This rearranged the periodic table by using the atomic number instead of atomic mass to represent the progression of the elements.
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Thomson had discovered the electron in a series of experiments. such as: using
'plum-pudding" -
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Aristotle had believed thet everything is made of four things such as: fire, earth, water, and air. These were also called four elements.