Across
- 2. it's in the fourth group and period five
- 5. it's atomic number is 12
- 8. atomic number:42 and it's mass number is 96
- 10. it's mass number is 89
Down
- 1. it's atomic number is 104
- 3. it's in the first group and period four
- 4. it's mass number is 178
- 6. it's mass number is 11
- 7. it's below argon
- 9. all living things need this