-
500 BCE
The Alchemists
The Alchemists discovered zinc and metallic arsenic -
460 BCE
Democritus
He theorized that all material bodies are made up of indivisibly small “atoms.” -
385 BCE
Aristotle
he invented the field of formal logic -
347 BCE
Plato
theoretical thought experiments to predict or postulate new concepts. -
Robert Boyle
as the person who discovered that the volume of a gas decreases with increasing pressure -
J.J Thomson
atoms contain tiny negatively charged subatomic particles or electrons -
Ernest Rutherford
a few are violently deflected, which implies a dense, positively charged central region containing most of the atomic mass -
Henry G. J. Moseley
this fundamental discovery concerning atomic numbers was a milestone in advancing the knowledge of the atom -
Werner Heisenberg
contributed to atomic theory through formulating quantum mechanics in terms of matrices and in discovering the uncertainty principle, which states that a particle's position and momentum cannot both be known exactly -
The Curies
Curie conducted her own experiments on uranium rays and discovered that they remained constant, no matter the condition or form of the uranium -
Neils Bohr
Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities
