-
500 BCE
The Alchemists
They discovered a way to turn common metals into gold -
428 BCE
Plato
Made up the table of elements -
400 BCE
Democritus
Made up a theory that everything was made up of small things called atoms -
Robert Boyle
Discussed the possibilities of atoms existing, he studied mainly gases.
He proposed that elements are composed of "corpuscles" of various sizes and types that can be able to organize themselves into -
Lavoisier
is most noted for his discovery of the role oxygen plays in combustion. He recognized and named oxygen and in 1778 he discovered hydrogen -
John Dalton
Proposed that compounds were atoms from different elements combined together and consisted of atoms that were identical and also had the same mass. -
Dmitri Mendeleev
Made the periodic table of elements -
JJ Thompson
Determined the charge to mass ratio of electrons -
The Curies
Discovered some atoms are radioactive -
Albert Einstein
Proposed the quantum of light in which he states that light is like a particle and also has a wave nature that is giving a dual nature. Also started the equivalence of energy and mass through the theory of special relativity -
Ernest Rutherford
Concluded a small, dense, positively charge nucleus as the result of the alpha particles scattering gold foil experim -
Neil Bohr
Proposed an atomic structure theory that stated the outer orbit of an atom could hold hold more electrons than the inner orbit -
Henry G. J. Moseley
Discovering that the number of protons in an element and its atomic number