Experiment 16.11: Concentration Dependency of Rate of Conversion
Acidified oxalic acid solution is mixed with differently diluted solutions of potassium permanganate.
The decolorizing process appears first in the most concentrated solution.
Purple permanganate ions are reduced in acidic solution by oxalate ions to the nearly colorless manganese(II) ions, whereas the oxalate ions are oxidized to gaseous carbon dioxide:
The higher the dilution, meaning the lower the concentration of the reactants, the more slowly the reaction proceeds.
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