Question

How to balance equations for reduction/oxidation reaction?

Answer 1

Before solving this question, we should first know about the Redox Reactions then we will be able to learn how to balance them. Reduction/Oxidation reactions also known as Redox reactions are the reactions in which one of the reactants is getting oxidized and another one is getting reduced.

Complete answer:
Balancing the redox equation can be a bit of a task. Let’s study about it.
The first step is to Identify the redox reactions. We have to see whether it is an even oxidation-reduction reaction. One needs to identify the reduced element as well as the oxidized one.
Once we identify the redox reaction we start balancing it – We have to add ${{H}_{2}}O$, ${{H}^{+}}$and ${{e}^{-}}$ in every equation, and adding stoichiometric coefficients in this manner:
Except for O and H, balance all the other elements in the equation
Then to balance the oxygen, we need to add water molecules (${{H}_{2}}O$) to the other side of the equation.
For Hydrogen atoms, we need to add ${{H}^{+}}$ions to the other side of the equation.
To make the charges equal, we add the number of electrons ${{e}^{-}}$ to the more positive side.
The number of ${{e}^{-}}$should also be equal, To make them equal we can multiply both sides by a number to make it the same.
Then we add the half equations together, and the electrons get canceled out and it gives us a one balanced equation. The common terms also get eliminated.
If we are using a basic solution to balance the equation then we have to add the number of $O{{H}^{-}}$ so that the ${{H}^{+}}$could get turned into ${{H}_{2}}O$ molecules.
Now, we can check whether the equation is balanced or not.

Note:
To balance redox reaction is much more difficult than to balance the standard chemical equations. The basic difference between balancing them is that we use the half Equation method in the redox reaction. We divide the equation into two parts. one performs oxidation, other performs reduction.