[01] Eni Generalić, Informatics Support Center, Faculty of Chemistry and Technology, University of Split, Split, Croatia. [02] Nives Vladislavić, Department of General and Inorganic Chemistry, Faculty of Chemistry and Technology, University of Split, Split, Croatia.

This paper presents a variation of the oxidation number change method for balancing redox equations that is applicable to any type of redox reaction including ionic and molecular reactions. The Aggregate Redox Species (ARS) method is particularly suitable for reactions that cannot be "cleanly" separated into partial reactions of oxidation and reduction. This method solves the problem by aggregating all species with redox atoms into one equation, balancing the redox atoms in them and "freezing" their stoichiometric coefficients. Non-redox species are added to the "frozen" equation (ARS equation), after which all other atoms and charges are balanced. A program developed based on the suggested method proved to be successful at solving a large variety of redox equations, thus demonstrating that the oxidation number change method is a systematical and highly applicable method for balancing redox equations.

Balancing Chemical Equation, Oxidation Numbers Change Method, Redox Reaction, Oxidation State, Stoichiometry, Computer-Based Learning

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