Lemon - My amazing crossword

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Across
  1. 4. used in medicine and important for the chemical industry
  2. 7. its spell similar to "california"
  3. 9. an air we need to breath in
Down
  1. 1. its taste salty when we eat it
  2. 2. its spell similar to "america"
  3. 3. put in balloon to make it fly
  4. 5. its the first word of one of the superhero
  5. 6. its expensive and people use it to make accessories
  6. 7. its help to repair and for growth of the body
  7. 8. used in toothpaste to prevent dental cavities