The First Periodic Tables :
The First Periodic Tables Dmitri Mendeleev Lothar Meyer
Importance of Periodic Table :
Importance of Periodic Table Used to predict the existence of elements not yet discovered
Showed that elements could be grouped in periods Mendeleev’s Periodic Table
Discovery of the Noble Gases :
Discovery of the Noble Gases Late 19th Century
William Strutt and William Ramsey added the noble gases to the periodic table
Henry Moseley :
Henry Moseley 1914
Was able to determine the number of protons(atomic number) in an atom
Periodic table based on atomic
number
Modern Periodic Table :
Modern Periodic Table Glenn Seaborg -Synthesized and identified elements 94-102 -Rearranged the periodic table by placing the
Actinide series below the lanthanide series Early 1940’s