Periodic Table Puzzle

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Across
  1. 3. nickel
  2. 6. mercury
  3. 8. tin
  4. 10. carbon
  5. 11. flourine
  6. 12. sodium
Down
  1. 1. zinc
  2. 2. chlorine
  3. 4. phosphorus
  4. 5. helium
  5. 7. lead
  6. 9. oxygen