Question

What happens to the number of valence electrons when we move down the group?

Answer 1

Valence electrons:

• The electrons that are present in the outermost shell of an isolated atom of an element are known as valence electrons.
• On moving down the group, there is no change in the number of valence electrons as the valency for all the elements present in the same group is same.

Example:

• Consider the alkali metals that belong to group $1$: $\mathrm{Li},\mathrm{Na},\mathrm{K},\mathrm{Rb},\mathrm{Cs}$ and $\mathrm{Fr}$.
• All these elements have the same number of valence electrons that is $1$.

Thus, the number of valence electrons moving down the group remains the same.