where are actinides found on the periodic table
Actinide The actinide /ˈæktɪnaɪd/ or actinoid /ˈæktɪnɔɪd/ (IUPAC nomenclature) series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium.[2][3][4][5]
History of the periodic table In 1817, Johann Wolfgang Döbereiner, a chemist, began to formulate one of the earliest attempts to classify the elements.[8] In 1829, he found that he could form some of the elements into groups of three, with the members of each group having related properties. He termed these groups triads.[9]