Is manganese(IV) oxide a catalyst? Hydrogen peroxide, H2O2 breaks down to form oxygen. This reaction is very slow without a catalyst. Describe an experiment to show that manganese(IV) oxide is a...
Is manganese(IV) oxide a catalyst?
Hydrogen peroxide, H2O2 breaks down to form oxygen. This reaction is very slow without a catalyst. Describe an experiment to show that manganese(IV) oxide is a catalyst for this reaction.
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Hydrogen peroxide solution
Hydrogen peroxide is a common oxidant with the chemical formula H2O2. It breaks down into water and oxygen gas according to the equation below:
2 H2O2 ---> 2 H2O + O2
This process is slow, however, and would take on the order of days and weeks just sitting on its own at room temperature. Manganese (IV) oxide, or MnO2, is a solid powder chemical that can help catalyze the reaction and make it take place over the course of minutes. The easiest way to see this happen is to simply add some solid MnO2 to an aqueous solution of H2O2. The MnO2 is a heterogeneous catalyst, meaning it does not dissolve in water and remains a solid. The chemical reaction occurs on the surface of the catalyst and so you will see the oxygen gas forming as bubbles that float out of the solution. If you take a wood splint and light it with the bunsen burner and hold the flame to the top of the solution, the flame will flare up due to the presence of the oxygen increasing the rate of combustion. You could also take a solution of hydrogen peroxide in a flask and weigh it on a balance, add MnO2 to allow the chemical reaction to take place, filter off the catalyst after the reaction is over, and re-weight the solution in the same flask on the balance. H2O2 is heavier than H2O, so the weight of the solution will have decreased as a result.