-
460 BCE
Democritus
Democritus said all matter was made of unbreakable things called atoms. -
John Dalton
John Dalton created three universal rules: all matter is made of atoms, atoms can’t be divided or destroyed, and all compounds are made of 2 or more types of atoms. -
Dmitri Mendeleev
Dmitri Mendeleev sorted all the atoms and put them into a chart called the periodic table. -
Eugene Goldstein
Eugene Goldstein discovered protons on the atom. -
J.J. Thomson
J.J. Thomson was able to discover electron surrounding the atom. -
Max Planck
Max Planck created the quantum theory. -
Robert Millikan
Robert Millikan was able to measure the charge of electrons in an atom. -
Ernest Rutherford
Ernest Rutherford believed that the nucleus was surrounded by empty space and electron circling it. -
Neils Bohr
Neils Bohr believed that the nucleus was positively charged and electrons orbited it in rings. -
Erwin Schrödinger
Erwin Schrödinger created quantum mechanical models that show the area of an atom that could contain an electron. -
James chadwick
James chadwick discovered that there were neutrons in the atoms. -
Werner Heisenberg
Werner Heisenberg created quantum mechanics.
