The main steps for balancing a redox reaction by this method are as follows:

Step I. Assign oxidation numbers of atoms undergoing oxidation-reduction and write separate equations for such atoms only.

Step II. Add electrons on the right side for oxidation and on the left side for reduction. The number of electron added in each case should be equal to the change in oxidation number.

Step III. Balance the number of electrons in the two equations and add the two equations to cancel out electrons.

Step IV. Then write the complete equation in its original form taking the co-efficient of the oxidants and resultants in Step III. Balance other atoms.

Step V. In acid medium, if oxygen (O) remains unbalanced, add water on the side deficient in O. If hydrogen still remains unbalanced then add H⁺ on the required side. Be sure that all participants and charges are balanced in the final equation.

Step VI. In basic medium, if oxygen (O) remains unbalanced, then add same number of H₂O as the unbalanced (O) atoms on the side with excess (O) and add double the number of OH ^- on the other side. This will balance oxygen.

In basic medium, if H remains unbalanced, then add same number of OH ^- as the difference on the side with excess H and add same number of H₂O on the other side.

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