symbols of elements.

1234567891011121314151617181920
Across
  1. 4. was discovered in 1803
  2. 6. i cost $10,000US per kilogram.
  3. 11. is shiny
  4. 12. is a noble gas
  5. 13. is radioactive
  6. 14. is the 7th most abundant element in the Earth's crust, accounting for about 2.5% of its mass.
  7. 16. Cave paintings dating from the Stone Age contained manganese pigments.
  8. 17. what makes you cry when you cut an onion
  9. 18. has a 110 protons
  10. 20. Polonium was named after her native country of Poland in an attempt to bring attention to its lack of independence.
Down
  1. 1. if you translated me from greek to english it means violet.
  2. 2. i create a glowing pale blue light.
  3. 3. i'm a heavy and dark liquid
  4. 5. in thermometer
  5. 7. on tanks
  6. 8. makes balloons fly
  7. 9. it glows in the dark
  8. 10. is the heaviest of all elements known to play a biological role.
  9. 11. has a boiling point of 5,131 F (2,833 C)
  10. 15. im one rarest things on earth
  11. 19. you use it to iron clothes