Answer:
B.They all have their valence electrons in the same type of subshell
Explanation:
- The electron configurations of elements in the same group (column) of the periodic table have them in the same type of subshell.
- But the subshells may be of different shells. Thus , the energies of them need not be the same.
- For example , The Alkalai Metals are found in the first column of the periodic table Group IA. This set of elements all have valence electrons in only the '
' orbital and because they are in the first column they all have
configuration. i.e,
- H
- Li
- Na
- K