0.2 of sample H2O2 reduced 20 ml of 0.1 M KMnO4 solution in acidic medium. What is the percentage purity of H2O2?


Correct option is



No. of moles of KMnO4 present in 20 ml of 0.1 M KMnO4 solution   

The balanced equation for the redox reaction is:


From the equation,

2 moles of KMnO4 ≡ 5 moles of H2O2


Mol. Wt. of H2O2 = 34

∴ Amount of H2O2 actually present = 34 × 5 × 10–3 = 0.17 g




In which of the following reaction, oxidation number of N remains unchanged?



KMnO4 acts as a strong oxidizing agent in acidic medium. The reaction that occurs is

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