11. Conservation of Mass,       Charge, and Energy   Previous PageNext Page
       Conservation of Electrons

The iron half-reaction is simple:

The final step is to add these two individually balanced half-reactions and obtain an overall reaction in which electrons do not appear explicitly. To accomplish this, we must add one unit of the manganese reaction to five units of the iron reaction. The result is the same as before:

This overall equation is now balanced with respect to charge and number of atoms because the half-reactions were balanced, and with respect to oxidation number because the proper multiples of the half-reactions were chosen to make the electrons cancel.

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