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The alchemists expand upon Aristotle's ideas by using elements as the basis of the universe which evolved into the modern periodic table of elements.
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Names the building blocks of the cosmos. Names them "atomos", which means indivisible -
Aristotle adds his own personal style by simple saying that the four elements (water, air, earth, and fire) are what makes up the universe, instead of atoms. -
After a long, long time, Robert Boyle comes up with a new idea that "corpuscles" made up everything. HIs research led to the confirmation of that idea, and his discoveries led to the eventual development of atomic theory -
John Dalton assigned masses to each of the 20 existing elements of his time. -
Re-arranged the periodic table in order of mass, and in doing so, developed the periodic law, which states "when the elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically." -
Discovered the electron, and went on to develop the first model of the atom. -
Theorized and proved that electrons have unchangable charges -
He discovered that atoms are mostly open space, with the majority of the mass being focused at the center of the atom. -
He developed the first version of a particle counter, and discovered the alpha particle, which is 2 protons and 2 neutrons in one nucleus. -
Discovered that electrons travel in separate orbits around the nucleus, the amount of electrons in the outer orbit determines an elements properties, and developed the model of the atom that we use today -
Discovered the existence of neutrons, proving that not all of the weight in an atom is the protons and electrons.