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ernast discovers the source of radioactivity
Ernest Rutherford discovered the source of radioactivity as decaying atoms -
Antoine Becquerel
Antoine Becquerel discovered that electrons and beta particles were the same thing. -
my boy ernest again
Ernest Rutherford established that “the nuclear charge on a nucleus was proportional to the atomic weight of the element.” -
niels bohr
Niels Bohr discovered the electrons' orbits and that there were more electrons in the outer orbits than in the inner orbits. He also saw that radiation was emitted when an electron would jump from one orbit to another. -
henery moseley made the atomic number for each element
Henry Moseley determined the atomic number of each of the elements and modified the 'Periodic Law'. -
ernast rutherford again
discovered protons in the nucleus. -
hernery moseley
labeled the elements with atomic numbers based upon the number of electrons in an atom rather than on their atomic mass. -
j.d cockroft
J. D. Cockroft and Ernest T. S. Walton worked together in splitting the atom when working with lithium which they bombarded with protons. The lithium nucleus was divided into two helium nuclei. -
Ernest O. Lawrence
Ernest O. Lawrence, Milton Stanley Livingston and Milton White worked on the first cyclotron at the University of California in Berkeley. A cyclotron is in the picture below. -
a van borek
A. van den Broek established that the atomic weight of an element was approximately equal to the charge on an atom. This charge became the “atomic number” by which periodic table elements are classified. -
Glenn Seaborg
Glenn Seaborg identified lanthanides and actinides which are elements with atomic numbers higher than 92 and are placed in a separate section on the bottom in today's Periodic Table. -
new elemets
there are 117 different elements. The most recent elements discovered are meitnerium, darmstadtium, and ununquadium.