Crossword puzzle

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Across
  1. 1. the weight of a atom
  2. 3. in milk
  3. 8. sub atomic particle with no charge
  4. 10. in blood
  5. 12. what jewelry is made from
  6. 13. crystals found in water
  7. 16. what we breath
  8. 17. more than one element
Down
  1. 1. Tightly packed atom
  2. 2. salty
  3. 3. what some cars are made from
  4. 4. what pennies are made from
  5. 5. what we drink
  6. 6. a building block of matter
  7. 7. bananas
  8. 9. element with one proton
  9. 11. a negatively charged subatomic particle that can be either bound to an atom or free
  10. 14. outer shell of an atom
  11. 15. a positively charged atom
  12. 18. what we drink from cows