Describe a simple test for the presence of a reducing agent using aqueous potassium manganate (VII) solution.

25/09/2020 at 4:33 pm (last edited 25/09/2020 at 4:33 pm)

Add a few drops of acidified potassium manganate(VII) solution to a solution containing an unknown agent.

If a reducing agent is present in the solution, the KMnO₄solution will turn from purple to colorless.

In the presence of a reducing agent, a redox reaction occurs, turning the Mn⁷⁺ ion in KMnO₄ (which is purple) to Mn²⁺ ion (which is colorless or slightly pinkish).