A chemical equation shows which reactants are converted into which products. Because of the law of conservation of matter, such an equation must be balanced. Stated in chemical terms, this means that the number of atomic particles of each occurring element must remain unchanged.Once it has been established by experiment that the given reactants can indeed be converted into the given products, chemistry has done its job. Balancing the equation of the reaction is a matter of mathematics only. One would, therefore, expect that all chemical equations are balanced in the same way. However, the number of articles on balancing chemical equations in general, and redox equations in particular, is quite large. Some of the proposed methods have even been given descriptive names. Thus, balancing may be accomplished by the "ping-pong method" (1), or by executing a "fair swap" (2).