Balence chemical equation and indicate types of chemical equation. ?

Question

MnO2 + H2O --> ?+?

Answer 1

Let's try this:

MnO2 + H2O2 --->

This is a classic demo. Look up the catalytic decomposition of hydrogen peroxide.

In other words:

2H2O2 + MnO2 ---> 2H2O + MnO2 + O2

The MnO2 is not actually consumed in the reaction since it is the catalyst. Usually, the MnO2 is written above the arrow, but I can't do that here. Here's an image showing what I mean:

https://image1.slideserve.com/2974733/slide7-l.jpg

Answer 2

There is no reaction between MnO2 and H2O.

(MnO2 and H2O2 react, but that is not what this question asked about.)