Across
- 3. Number of protons
- 4. Likely to decay
- 6. Charged atom or group
- 8. Vertical column in table
- 9. Protons plus neutrons
- 11. Group 17 nonmetals
- 13. Radioactive series
- 15. Time for half to decay
- 17. Horizontal row in table
- 20. Neutral atomic particle
- 21. Positively charged ion
- 22. Energy level of electrons
- 23. Poor conductor element
Down
- 1. Atomic core
- 2. Positive charge particle
- 3. Group 1 metals
- 5. Rare earth series
- 7. Metals in center of table
- 10. Good conductor element
- 12. Unstable nucleus emitting radiation
- 14. Negative atomic particle
- 16. Electron path
- 18. Between metal and nonmetal
- 19. Energy from unstable atoms
- 22. Not likely to change