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Coloured precipitates

Identify metal ions from the colour of their hydroxides, and sulfate with barium.

Topic: Identifying substancesGrade: 10Free

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What you do

  1. Add sodium hydroxide to tube 1 (Cu²⁺).
  2. Add sodium hydroxide to tube 2 (Fe³⁺).
  3. Add sulfuric acid to tube 3 (Ba²⁺).
  4. Bonus: add hydrochloric acid to tube 1. What happens to the blue precipitate?

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