Across
- 2. Energy level of electrons
- 3. Group 17 nonmetals
- 7. Negative atomic particle
- 11. Positive charge particle
- 13. Electron path
- 14. Likely to decay
- 15. Not likely to change
Down
- 1. Time for half to decay
- 4. Unstable nucleus emitting radiation
- 5. Radioactive series
- 6. Metals in center of table
- 8. Rare earth series
- 9. Neutral atomic particle
- 10. Atomic core
- 12. Energy from unstable atoms