Respuesta :
Valence electrons can be found by determining the electronic configurations of elements. Thereafter the number of electrons in the outermost shell gives the total number of valence electrons in that element.
Answer:
You can tell by the group number of the element.
Explanation:
E.g. potassium (K) has one valence electron (one electron in its outer shell) because it is in group one.
Hope this helps!