Building Blocks

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Across
  1. 2. ​​the basic building blocks of all materials.
  2. 3. When a molecule is made up of two or more different types of elements chemically combined
  3. 4. H is the ____ for hydrogen
  4. 6. a substance made up of only one type of atom​
Down
  1. 1. formed when 2 or more atoms of the same element chemically combine
  2. 5. the _____ table shows a list of all the elements​