1. explain how groups 1a-8a in the periodic table are organized by their number of valence electrons.
3. explain how you know the # of valence electrons for each group.

Ithink it’s one of those things that you put the object on

16- counting by fours

☆ionisation energy increases across a period from na -> ar☆ionisation energy decreases down a group from li -> fr☆ionic radius decreases across a period from na -> cl☆ionic radius increases down a groupfrom f -> ii hope it clarifies your doubts