Across
- 3. 6 neutrons
- 6. atomic mass of twelve
- 8. fifteenth group and fourth period
- 9. fifth period in the halogens family
- 11. atomic symbol U
- 12. forty-three protons
- 15. fourth period in the eighteenth group
- 17. metal with 58 electrons
- 19. thirty-one electrons
Down
- 1. first period in the first group
- 2. atomic mass of a hundred and thirty-one
- 4. fourth period in the second group
- 5. atomic symbol of Cs
- 7. metal with twelve neutrons
- 10. atomic symbol V
- 13. tenth group in the fourth period
- 14. atomic number of twenty-nine
- 16. metalloid in the sixth period
- 17. atomic mass of fifty-nine
- 18. seventh period in the alkaline family