Across
- 2. it's just fire
- 5. is the symbol of TH on the periodic table
- 8. the most poisonous element
- 9. it's something a blant breathes in
- 11. very precious and are worth more than gold
- 13. this element group consists of fluorine
- 15. second lightest element
Down
- 1. poisonous and the heaviest on the periodic table
- 3. All in this group are radioactive and release energy upon radioactive decay
- 4. symbole of B with the atomic number 5
- 6. most reactive chemical element
- 7. this has the atomic number four with the symbole of BE
- 10. without it, we would die
- 12. 69th element on the periodic table
- 14. used in electric signs and fluorescent lamps