Chapter 12 Puzzle

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Across
  1. 3. in chemistry, a horizontal row of elements in the periodic table
  2. 6. one of the elements of group 2 of the periodic table
  3. 7. one of the elements of group 17 of the periodic table
Down
  1. 1. law that states that the repeating chemical and physical properties of elements change periodically with the atomic number of the elements
  2. 2. one of the elements of group 18 of the periodic table
  3. 4. a vertical column of elements in the periodic table; elements in a group share chemical properties
  4. 5. describes something that occurs or repeats at regular intervals
  5. 6. one of the elements of group 1 of the periodic table