Across
- 3. _______ number indicates the valance electrons
- 8. The designer of the periodic table of elements
- 9. Indicates the number of energy levels
- 10. Most abundant metal in earth’s crust
Down
- 1. Added to toothpaste and drinking water to protect tooth enamel from decay
- 2. Group 7A on the periodic table
- 4. The number of non metal elements on the periodic table of elements
- 5. Found widely in nature- rocks, coral reefs
- 6. Can be found in quartz crystal, sand, and glass
- 7. Used in blimps, airships, and balloons