Across
- 2. the emissions of radioactive particles
- 4. a highly conductive element
- 6. total number of protons and neutrons in a nucleus
- 7. formed when an atom gains an electron
- 10. the number of neutrons in a nucleus
- 13. a positively charged particle
- 15. formed when an atom loses an electron
- 16. when unstable atoms lose energy by radiation
- 18. rare earth metals
- 21. all are radioactive
- 23. elements on the right side of the periodic table
- 24. an uncharged particle
- 25. the number of protons in a nucleus
Down
- 1. a row of chemical elements in the periodic table
- 3. reactive with Group 17
- 5. good conductors
- 8. VERY stable, colorless and odorless
- 9. a negatively charged particle
- 11. formed when an atom gains or loses 1 or more electrons
- 12. a column of elements in the periodic table
- 14. an element with properties between metals and nonmetals
- 17. VERY reactive with Groups 1 and 2
- 19. found in the center of an atom
- 20. VERY reactive with Group 17
- 22. model predicts where electrons will move