Across
- 3. can be observed without being changed
- 7. liquid turning into vapor
- 9. one kind
- 12. a gas
- 14. a group of atoms held by covalent bonds
- 15. changes
Down
- 1. siblings of atoms
- 2. substance turning into a new substance
- 4. space
- 5. measurement
- 6. temperature whicha liquid boils
- 8. smallest unit
- 10. doesnt change
- 11. force
- 13. where elements are located