The equation is 4KMnO4 + 12H2C2O4 -> 4K2C2O4 + 12MnSO4 + 8H2O.

The above chemical equation describes the reaction process between potassium permanganate (KMnO₄) and oxalic acid (H₂C₂O₄) to form potassium oxalate (K₂C₂O₄), manganese sulfate (MnSO₄), and water (H₂O). According to the balanced equation, 4 mol of KMnO₄ requires 12 mol of H₂C₂O₄ to produce 4 mol of K₂C₂O₄, 12 mol of MnSO₄, and 8 mol of H₂O.

Reaction conditions: This reaction occurs in an acidic environment, typically using sulfuric acid (H₂SO₄) as the medium.

Reaction process: Potassium permanganate in an acidic environment will be reduced to manganese ions (Mn₂+) by oxalic acid. In this process, oxalic acid is also oxidized to oxalate ions (C₂O₄₂-). Potassium from KMnO₄ and oxalate from H₂C₂O₄ will combine to form potassium oxalate. The manganese ions and sulfate ions from the acidic environment will combine to form manganese sulfate.

Phenomenon occurs: Potassium permanganate is purple, and when reacting with oxalic acid, it produces pale pink manganese sulfate and colorless potassium oxalate. Therefore, the color of the solution will change from purple to pale pink, and finally to colorless.