-
450
introduced the concept of the atom
Democritus 450 - 420 B.C. -
450
The old bouleuterion
the west side of the agora in Athens, is built -
Sep 18, 1000
orbitals
-
Sep 18, 1100
energy levels
-
Sep 18, 1200
protons and neutrons
-
Sep 18, 1300
nucleus
-
Sep 18, 1400
electrons
-
Sep 18, 1500
concept of the atom
-
discovered that electrons move in orbitals
Bohr Neils Henrik David by investigating atomic structure and radiation -
!st meteor
The 1st meteor is photographed -
discovered atoms have electrons
J.J. Thompson, he discovered it by the Atomic Theory of Matter -
San Diego State
San Diego State University is founded. -
discovered atoms have a nucleus
Earnest Rutherford by using gold foil expirament -
Tripolitan War
he Italians declared war on Turkey in September. -
discovered that atoms are at different energy levels
Neils Bohr by observing the spectral lines of emitted radiation when the atoms are excited -
Woolworth Building
The skyscraper Woolworth Building in New York City is opened. -
discoved that there are protons
Ernest Rutherford, by an expirament that sent alpha particles through nitrogen gas. -
Mississippi and 18th amemndment
Mississippi becomes 1st state to ratify 18th amendment -
Discovered Neutrons
James Chadwick by a series of expiraments
