Dawson Tullos puzzle

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Across
  1. 2. individual component of a larger or more complex whole
  2. 6. liable to change rapidly and unpredictably
  3. 8. multiplier for converting a quantity expressed in one set of units into an equivalent expressed in another.
  4. 9. without a clearly defined shape or form
Down
  1. 1. mass per unit volume
  2. 3. set of principles that try to explain something
  3. 4. measure of the amount of matter
  4. 5. a substance that takes part in and undergoes change during a reaction.
  5. 7. the basic units of matter and the defining structure of elements