Answer:
A barium atom would be expected to contain 2 electrons in its outer energy level.
Explanation:
The columns of the periodic table are called groups. There are eighteen groups, numbered from 1 to 18.
The elements of each group have the same number of electrons in their last atomic shell, which is why they have similar chemical properties, because the chemical properties of chemical elements are strongly related to the electrons located in the last atomic shell.
That is, in a group, the chemical properties are very similar, because all the elements of the group have the same number of electrons in their last or last shells.
A barium atom would be expected to contain 2 electrons in its outer energy level.
