-
330
Aristotle
He proposes the four element theory; earth, air, fire, and water 330 B.C -
360
Plato
He makes the term â€~elementsâ 360 B.C -
440
Democritus & leucippus
They proposed the idea of the atom, and invisible particle that all matter is made of. 440 B.C -
Robert Boyle
He published "The Sceptical Chymist" which was a treatise on the distinction between chemistry and alchemy. It also contained some of the earliest ideas of atoms, molecules, and chemical reaction marketing the beginning of the history of of modern chemistry -
John Newlands
Arranged the known elements in order of atomic weights and observed some similarities between some elements -
Lothar Meyer
Develops an early version of the periodic table, with 28 elements organized by valance -
Dmitri Mendeleev
He produced a table based on atomic weights but arranged "periodically" with elements with similar properties under each other. His periodic table included the 66 known elements organized by atomic weights -
Jakob Berzelius
Developed a table of atomic weights & introduced letters to symbolize element -
Johann Donereiner
He developed groups of 3 elements with similar properties