Question

by product when potassium permanganate and hydrogen peroxide combined

Answer 1

3H2O2 + 2KMnO4 → 3O2 + 2MnO2 + 2KOH + 2H2O

Answer 2

When hydrogen peroxide is mixed with potassium permanganate, oxygen gas and water vapour are formed, according to the reaction

2MnO4−+3H2O2⟶2MnO2+2H2O+3O2+2OH−2MnOX4X−+3HX2OX2⟶2MnOX2+2HX2O+3OX2+2OHX−

This reaction is spontaneous, and exothermic. It is an example of a redox reaction, with the following half reactions occurring

MnO4−+2H2O+3e−⟶MnO2+4OH−(E∘red=0.595 V)MnOX4X−+2HX2O+3eX−⟶MnOX2+4OHX−(Ered∘=0.595 V)

H2O2⟶O2+2H++2e−(E∘ox=−0.695 V)HX2OX2⟶OX2+2HX++2eX−(Eox∘=−0.695 V)

E∘cellEcell∘ is equal to the sum of the oxidation potential and the reduction potential of the two half reactions; in this case, it would be −0.1 V−0.1 V. A redox reaction is spontaneous if E∘cellEcell∘ is positive