Across
- 3. nucleus
- 5. substance
- 7. nucleus
- 8. combination
- 11. shoing elements
- 14. two variants
- 15. number
- 16. what everything is
- 17. change can see difference
- 19. small electricity
- 20. total number
Down
- 1. no difference
- 2. center
- 4. obvious
- 6. material with buddies
- 9. pure substance
- 10. amount of matter
- 12. thickness
- 13. catch on fire
- 16. mass
- 18. column on table