Across
- 4. the catagory that is between metals and nonmetals
- 5. positively charged particle
- 7. negatively charged particles
- 8. number of rows on the periodic table
- 9. the catagory that "helium" is in
- 13. elements that are harmful to humans
- 17. mendeleev father of the periodic table
- 18. neutral particals
- 20. name the name of an element
Down
- 1. the catagory that "iron" is in
- 2. the first element in the periodic table
- 3. can the substance be ignited?
- 6. orbitals
- 10. how reactive a substance is
- 11. located on the periodic table
- 12. the number of groups on the periodoc table
- 14. mass total number of protons + neutrons
- 15. one way to determin how many valence electrons an element has
- 16. number the number of protons in an element
- 19. metals the first family in the periodic table