Share
Explore BrainMass

Balancing redox equations by the oxidation number method

2KMnO4 + 5H2O2 + 6HCl --> 5O2 + 2MnCl2 + 8H2O + 2KCl

I need to calculate the balanced NET IONIC equation for the above reaction.

I've been using the oxidation number method and determined H2O2 is the reducing agent and KMnO4 is the oxidizing agent.

Mn gained 5 electrons, but I'm not sure how many electrons Oxygen gained, I'm thinking one electron but the two different oxygen oxidation numbers in the products are throwing me off. I know I need to make the electrons lost equal the electrons gained. My problem is that I'm not sure about the number of oxygen electrons gained and then I'm not sure on which compounds containing oxygen I should apply the coefficient to.

Am I even using the right approach?

Solution Preview

To answer this question one must first assign oxidation states for each individual element. Potassium (K) is a spectator, along with Cl, and H takes no part in the redox reaction. We can see that Mn gains 5 electrons, and it must do so by taking them from the peroxide (HOOH). What I would do is to separate both the oxidation and the reduction, and ...

Solution Summary

This answer is provided in 288 words and explains how to balance an equation using oxidation states and step-by-step balancing of the reaction.

$2.19