MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Potassium permanganate titration. Here, as purple potassium permanganate is added to clear oxalic acid the reaction has slowed down and the solution has turned brown. Warming the solution to 85 degrees Celsius or adding sulphuric acid, will avoid this problem. The reaction will speed up and the solution will clear again.
Model release not required. Property release not required.