History of Atomic Theory

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    John Dalton

    John Dalton was born in 1766. Dalton came up with an atomic theory which was that all matter is made up of atoms, all atoms of an element are identical in both mass and properties, compounds are formed by a combination of two or more different kinds of atoms and that a chemical reaction is like the repositioning of atoms. He made these discoveries in 1803.
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    Marie Curie

    Marie Curie was born on 7th November in 1867 in Warsaw, Poland. She discovered methods for seperation of radium from radioactive which allows us to now characterise and study it’s properties, not only did she do this but discovered that atoms ability to emit rafiation depends on it’s interior. She discovered 2 radioactive elements which were Radium and Polonium.
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    Ernest Rutherford

    Ernest Rutherford was born on 30th August 1871 in Nelson, New Zealand. He discovered the nucleus of an atom which then became an important part of the model of an atom. His diagram of the atom was simplified, showing electrons circling around the nucleus as well as his discovery of the proton in 1899. Later in 1908 he was awarded the Nobel Prize for the change of elements, and in honour, the element “Rutherfordium” was named after him
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    Niels Bohr

    Niels Bohr was born on 7th October 1885 in Copenhagen, Denmark. In 1913 he looked at the structure of atoms and it’s nucleus based on what Rutherford had already discovered about atoms and began looking further into their structure. His greatest contribution was the modern physics atomic model. He also discovered that electrons travel in separate orbits around the nucleus of the atom and that the number of electrons in the outer shell determines the properties of the element.
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    Henry Moseley

    Henry Moseley was born on the 23rd November 1887 in England. He later became a Physicist and Henry created the modern day periodic table. He also created the atomic numbers for elements on the periodic table and made these amazing discoveries in 1913
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    Francis Aston

    Francis William Aston was born on 1st September, 1877 in England. Aston was a British chemist, physicist and Nobel Prize winner. He was awarded his Nobel Prize in 1922 for his invention of the mass spectrometer which is an used for separating isotopes and molecules. He also discovered isotopes and the ‘Whole Number Rule’ for isotopes.
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    Erwin Schrodinger

    Erwin Schrodinger was born on 12th August 1887, Vienna, Austria. He was the man behind the formula for the wave-equation that gave you an accurate energy level of atoms. Schrodinger also created an atomic model known as the quantum mechanical model of the atom. His model didn’t define the exact path of an electron however instead would predict where and atom could be.
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    James Chadwick

    James Chadwick was born on 20th October in 1891. Chadwick proved the existence of neutrons. He discovered that the atomic number is based on the number of protons in an atom. The thing that he was most famous for was the discovery of the neutron in an atom which happened in 1932.
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    Murray Gell-Mann

    Murray Gell-Mann was born on 15th September 1929 in New York City. He discovered the quark which is a fast moving point of energy and all protons and neutrons have 3. There were 3 types of quarks which are up, down and strange. He also made the method called the Eightfold Way which was used for the periodic table.