1.) Nonmetallic elements form ions by (Losing/Gaining) valence electrons in order to complete their outer shell. 2.) The (Fewer/More) valence electrons an element has in its outer shell, the easier it is to complete. 3.) The (FewerMore) electron shells an element has, the easier it is to fill its outermost shell. 4&5.)Reactivity in nonmetals (Increases/Decreases) as you go from left to right in a group, and (Increases/Decreases) as you go from top to bottom.

1) Gaining

2) More

3) More

4) increases

5) decreases

Explanation:

Nonmetals are found towards the right hand side of the periodic table. They form ions by gaining electrons due to the fact that they have more electrons in their outermost shell, hence they only need a few electrons to complete the octet structure.

As the number of shells increases, the outermost shell becomes more populated and easier to fill with electrons.

The reactivity of nonmetal elements generally increases from left to right across the periodic table but decreases from top to bottom down the group.