Glenn Seaborg reordered the Periodic Table- put the actinide series below the lanthanide series. (9 ч 26 мин, 1 янв 1940 г. – 0 ч 3 мин, 31 дек 1940 г.)
Описание:
Actinide- Atomic numbers from 89-103. 15 elements, named after Actinium, first element in series. Used in nuclear reactors and bombs.Lanthanide- Atomic numbers from 57-71. 15 metals, rare earth elements. Silvery-white metals, similar to Lanthanum, first element in group. Found naturally on Earth.
"Inner Transition Elements". Rare elements listed at bottom of Periodic Table.
Добавлено на ленту времени:
Дата:
9 ч 26 мин, 1 янв 1940 г.
0 ч 3 мин, 31 дек 1940 г.
~ 12 months