Across
- 2. a negatively charged particle
- 3. metals group 1 on the periodic table; very reactive
- 4. the number of protons in the nucleus of an atom
- 6. group 2 on the periodic table; reactive
- 8. a positively charged particle
- 9. the central core of an atom
- 10. group 17 on the periodic table; very reactive
- 11. the mass of an atom of an element
Down
- 1. a chart of the elements showing repeating patterns of the elements
- 5. a small particle in the atom's nucleus with no electrical charge
- 7. group 18 on the periodic table; do not bond