Question

Hydrogen peroxide (`H_2O_2`) naturally breaks down into `H_2O` and `O_2` over time. When manganese dioxide (`MnO_2`) is added, the rate of this reaction increases. Based on this information, what can be hypothesized?

Answer 1

That `MnO_2` catalyzes the decomposition of hydrogen peroxide.

Explanation:

`H_2O_2 rarr H_2O + 1/2O_2`

This reaction has a measurable rate, and in the presence of `MnO_2`, this rate is faster. Since, by definition, a catalyst modifies reaction rate, the added oxide has acted as a catalyst, and provided an alternative reaction pathway.