Answer:
H- hydrogen
Explanation: Hydrogen is in the first group meaning that it only has 1 valence electron and 1 energy level
1.Calcium Chloride
2.Lithium Bromide
3.Beryllium Sulfide
4.Lithium Fluoride
5. Potassium hydroselenide
6. Strontium phosphide
7.Barium Chloride
8.Iron Oxide
9.Iron
10.?
11.Copper Nitride