Difference between revisions 469049484 and 469049550 on enwiki

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! scope="col" style="width: 1.0%;" | [[Periodic table group|Group]] #
! scope="col" style="width: 5.5%;" | [[Alkali metal|1]]
! scope="col" style="width: 5.5%;" | [[Alkaline earth metal|2]]
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* {{colorbox|#FBCB83}} 1850–1899 (26 elements):  the age of [[History of the periodic table#Classifying Elements|classifying elements]]; application of [[Spectrum analysis#Origins|spectrum analysis]] techniques: Boisbaudran, Bunsen, Crookes, Kirchhoff, and others "hunting [[emission line]] signatures".
* {{colorbox|#AAD26E}} 1900–1949 (13 elements):  development of [[old quantum theory]] and [[quantum mechanics]].
* {{colorbox|#6CACDE}} 1950–1999 (16 elements):  
"post atomic bomb" eraManhattan project; [[Synthetic element|synthesis]] of atomic numbers 98 and above ([[collider]]s, bombardment techniques).
* {{colorbox|#FC86F6}} Since 2000 (5 elements): recent synthesis.
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[[Category:Periodic table]]
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