Elements in group 1 and group 2 are metals. Atoms of group 1 elements have one electron in their outer shell, and atoms of group 2 elements have two electrons in their outer shell. Elements in ...

Elements in the same horizontal row are in the same period. The periods are numbered from top to bottom. The period number is the same as the number of occupied electron shells.

Uranium, belonging to the periodic table's actinide elements, has long intrigued scientists due to its complex electron configurations ... electrons in its inner shells compared to other, more ...