-
400 BCE
democritus
everything is composed of atoms
by imaging the sign of the first atom -
400 BCE
plato
ideal geometric forms serve as atoms -
1197
JJ thompson
discovered the electron
all matter is type of particle smaller than atom -
1200
Antone Lavoisier
law of conservation
father of chemistry -
1400
The alchemists
-Treated other ores and metals to make gold
-created a scientific theory that eventually discovered the atom -
Robert boyle
contributed to development of corpusculums. -
John Dalton
-English chemist and physicist who proposed first modern atomic theory -
Amadeo Avogradro
equal volumes of gases under the same conditions of tempeture and pressure -
Dmitri Mendeleev
made first periodic table
discovered elements not yet found -
Pierrre and Marie Curie
conducted research or radiology
discovered polonium and radium -
Albert Einstein
mathematically proved the existence of atoms and their random, ceasless motion -
robert millikan
figured out charge of the electron -
ernest rutherford
a pioneering researcher in both atomic and nuclear physics -
Neils Bohr
-Atomic theory states that an atom is like a planetary model where electrons were situated in discreetly energized orbits -
henry g. j mosely
discovered atomic numbers of each element -
James Chadwich
discovered the neutron