Across
- 2. a reddish metal with a face-centered cubic crystalline structure
- 5. the cosmic product of burning helium
- 8. atoms of the same element with different numbers of neutrons
- 10. negative particle in the nucleus
- 11. has a density lower than any metals
- 14. Gases or dull brittle solids
- 17. The vertical columns on the periodic table
- 19. solids or semiconductors
- 20. abbreviation for the name of the element
Down
- 1. a clean alternative to methane
- 3. positive particle in the nucleus
- 4. type of electrolyte
- 6. a nonmetallic element of the group 15
- 7. makes balloons rise
- 9. the smallest particle of an element
- 12. shiny silvery solids and good conductors
- 13. negative atom in the neucleus
- 15. number tells the number of protons and neutrons in the nucleus
- 16. found in many foods and has an atomic mass of 23
- 18. the horizontal rows on the periodic table