Title
Across
- 1. related to Neutron
- 4. NaH
- 6. Gas, Solid, liquid
- 7. two outside the cloud
- 9. Non Explosive
- 11. Number
- 13. Explosive
- 14. Iron
- 15. o for oxygen
Down
- 2. related to Proton
- 3. Elements arranged in a group
- 5. the center
- 8. brave gas
- 10. Mass
- 12. Gas