chemical puzzle

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Across
  1. 3. electron the second row of the energy level
  2. 6. the smallest thing in the world
  3. 7. not the hard stuff found underground
  4. 8. easily breaks
  5. 10. the hard stuff found underground
Down
  1. 1. bigger than a atom
  2. 2. the big table of elements
  3. 4. the science that deals with the identification of matter
  4. 5. mass
  5. 9. shiny