Across
- 3. quantum mechanics
- 6. planet-like orbits
- 10. a particle and a wave
- 12. lowest energy state
- 15. colored lines
- 18. higher energy levels
- 19. nobles gases
Down
- 1. electrons must fill the-
- 2. principal energy levels
- 4. illustrate the electron-
- 5. special electrons
- 7. planetary model
- 8. first formulated-
- 9. electrons in a atom
- 11. energy shells
- 13. dots that represent-
- 14. positive ions
- 16. as electrons fill a sublevel
- 17. massless particles
- 20. negative ions