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465 BC. Democritus was the first to propose that matter exists in the form of particles. He also coined the term 'atoms'.
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1000-1600 BC The process that enabled man to turn lead and other materials into gold was known as alchemism. Alchemists also tried to create an elixir that would prolong life and used plant derived-materials to cure diseases.
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Big B.Berzelius was the first to classify various minerals according to their chemical composition. He also aided in the discovery and further study of many known elements such as selenium, silicon, and zinc.
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1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms. http://www.iun.edu/~cpanhd/C101webnotes/composition/dalton.html -
Discovered noble gases which fill a large portion of the periodic table and helped construct models of chemical bonding.
Big Will! -
The first Nobel Prize in Chemistry was awarded in 1901 to Jacobus Henricus van’t Hoff, of the Netherlands, "for his discovery of the laws of chemical dynamics and osmotic pressure in solutions."
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Suggested a model of the atom as a sphere of positive matter in which electrons are positioned by electrostatic forces. http://www.daviddarling.info/images/Thomson_atomic_model.gif
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The planetary model of the atom which put all the protons in the nucleus and the electrons orbited around the nucleus like planets around the sun. http://en.wikipedia.org/wiki/File:Rutherfordsches_Atommodell.png
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Atom resides in the center (positively charged nucleus) with electrons that flow in a circular motion around the nucleus. http://www.rsc.org/chemsoc/timeline/graphic/1913_bohr2.jpg
