Reactivity Patterns in Group 1 and Group 7 Elements

• THE HIGHER THE NUMBER OF VALENCE SHELLS…
• THE MORE EASILY THE ELECTRONS ARE LOST AND
• THE LESS EASILY THE ELECTRONS ARE GAINED

• As you go down Group 1, reactivity increases. The valence electron gets further from the nucleus so its attraction to the nucleus is weakened, making It is easier to lose.

• As you go down Group 7, reactivity decreases. There are less shells higher up Group 7 so the nucleus is closer to the region outside of the element, making it easier to attract electrons. As the number of shells increases, the nucleus is farther away from the region outside of the element so it is harder to attract electrons.