Final answer:
The purpose of finding oxidation states in the half-reaction method for balancing equations is to make sure the equation is balanced electrically. The half-reaction method involves breaking down the overall equation into two separate half-reactions, balancing each half-reaction for atoms and charge, and then recombining them to form the balanced equation. An example is given to illustrate the process.
Step-by-step explanation:
The purpose of finding oxidation states in the half-reaction method for balancing equations is to make sure the equation is balanced electrically (c).
In the half-reaction method, the overall equation is broken down into two half-reactions. Each half-reaction is balanced separately, first for atoms and then for charge. Electrons are added to one side of the equation or the other in order to balance charge. Finally, the two half-reactions are added together, and any spectator ions that were removed are placed back into the equation.
For example, consider the reaction:
Fe2+ + MnO4- -> Fe3+ + Mn2+ (in acidic solution)
In this reaction, the iron ion Fe2+ is oxidized to Fe3+, and the manganese ion MnO4- is reduced to Mn2+. By assigning oxidation numbers to each element and balancing the half-reactions for atoms and charge, the equation can be balanced.