This article is about Aktinum. The presence of superranium elements was proposed by Enriko Fermi in 1934.However, people did not understand the concept that the Actinum was only four elements at that time, and it became similar to the Lantanum.The argument that was dominated at that time was that the ultra -lanium should enter the seventh cycle, not the Actinum.Thorium, proprietary and uranium should be under the six cycles, which should be under Harfnium, Tantalum and Tungsten.The synthesis of superranium gradually dug up the center of the Axinium.In 1944, in order to complete the Actinum hypothesis, Glen T. Sibogg observed the failure to test oxidation of more than 4 oxidation of oxidation.(It was estimated to be under the 6th cycle, because it was possible, because the platinum was possible up to 6.)The sentence "Aktinium hypothesis" (the influence of the hypothesis ”has not been decisively demonstrated) remains and is actively used by scientists in the late 1950s.
When is the "Actinum hypothesis" actively used by scientists?
Late 1950s