The method describes how to determine the manganese content of water photometrically with a cuvette test.
Manganese(II) ions react in an ammonia solution with formaldoxime, forming a reddish-colored complex.
The method describes how to determine the manganese content of water through oxidation to permanganate.
Manganese ions are catalytically oxidized into purple-colored permanganate ions. The purple color of the solution is determined using a comparator (or photometrically):
Mn2+ + 12 H2O → MnO4- + 8 H3O+ + 5 e-