Periodic Clues

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Across
  1. 2. The most abundant element in the universe
  2. 4. This group I metal bursts into flame if it hits water
  3. 5. The first ever laser beam was made from a ________ ruby
  4. 7. The German word for Tungsten
  5. 8. Along with phosphorous, used in many plant fertilizers
  6. 9. When burned in fireworks, this poisonous element turns them blue
Down
  1. 1. Iron, cobalt and nickel are all _________ transition metals
  2. 3. One of the two elements used in atomic clocks
  3. 4. When mixed with gold, turns it into white gold
  4. 6. Sea creature from which the ancient Romans collected bromine for their purple fabric dye