jan 1, 1913 - NIELS BOHR (1885-1962 CE)
date of discovery (1913 CE)
Atom is composed of negatively
charged electrons traveling in
separate orbits around a positively
charged nucleus. Atoms absorb or
emit radiation when electrons on
subatomic level jump between the
allowed and stationary states.
Discovered that the number of
electrons in the outer orbit
determines the properties of an
element.
Bohr’s work contributed significantly
to scientists' understanding of nuclear
fission.
