Across
- 2. group I metal
- 5. the vertical columns are called families or ...
- 7. the sum of the protons and neutrons is the ... number
- 8. nonmetals tend to form ... ions
- 9. inactive gases
- 10. most active nonmetals
- 12. the horizontal rows are called ...
- 13. most of the elements are ...
Down
- 1. group II metal
- 3. elements in the middle of the periodic table are the ... metals
- 4. metal tend to form ...
- 6. atomic number is the number of ..
- 11. the elements are arranged by atomic