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500 BCE
The Alchemist
They discovered that by breaking down the chemical proportion of the 4 basic elements of its period, fire, earth, wind and water eventually evolved into the periodic table -
427 BCE
Plato
He came up with the elements and argued that atoms could never produce the form of the world -
400 BCE
Democritus
He proposed that atoms were uniformed, hard, solid, icompressible and moved in infinite numbers -
Robert Boyle
Proposed that elements are made of curpuscles that vary sizes and types can organize themselves in groups that represent different chemical substances -
Antone Lavoisier
He proved the conservation of matter -
John Dalton
He proposed the atomic theory, which stated that all matter was composed of atoms, indisivle and indestructible building blocks -
Amadeo Avogrado
He proposed that gases such as hydrogen, nitrogen and oxygen were composed of two atoms -
Dmitri Mendeleev
He desvised the clasification of the chemical elements and they are arragend in base on their atomic weight -
Jj Thompson
He discovered the electron and proposed a model for the structure of an atom -
Pierre and Marrie Curie
Discovered strongly elements polonium and radium, which occur in minerals made of uranium -
Albert Einstein
He proved the existence of atoms mathimatecaly -
Robert Millikan
He tested an experiment called oil drop, where he discorvered the charge of an electron -
Ernest Rutherford
He discovered atoms have a small charged nucleous that is surrounded by empty space and tiny atoms circle them -
Henry G.J. Mosely
He found
out that the number of x-ray radiaton has a mathematical relationship to an element's atomic number -
Neils Bohr
He proposed the hydrogen atom, which stated that electron move around their nucleous, only in an orbit, and if they are moved to a lower energy orbit the difference is going to be sent as a radiation -
Erwin Schrondinger
He devised the quanzitation of an hydrogen atom's energy levels that appeared in Neils Bohr atomic model could be calculated from Schrondinager's equation -
Werner Heisenberg
He formulated quantum mechanics in terms of matrices -
James Chadwich
He discovered the neutron