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Blood-red test for iron(III)

Thiocyanate ions find even a trace of Fe³⁺.

Topic: Identifying substancesGrade: 10Free

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What you do

  1. Add potassium thiocyanate to tube 1 (iron(III) chloride).
  2. Add it to tube 2 (copper(II) sulfate) as a control.
  3. Tube 3 is almost colourless — but it contains a trace of Fe³⁺. Test it.

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