Period 8 element

• abstract: A period 8 element is any one of 46 hypothetical chemical elements (ununennium through unhexquadium) belonging to an eighth period of the periodic table of the elements. Sometimes, elements 169 to 172 are also considered to be in period 8 as their outermost electrons fill the 8p3/2 subshells, despite behaving chemically more like the period 9 elements.

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