Using the Carbon-Atom Method to Determine Mean Oxidation Number of Organic Carbons

Abstract

The notion of oxidation number acting as an electron-counting concept is crucial for balancing redox reactions, and for understanding organic and biological redox conversions. Chemical formula methods are widely used for counting oxidation numbers. There are three types of chemical formula methods. They are molecular formula method, structural formula method, and Lewis formula method. Each type has its own rules and procedures, and they are difficult for students to fully understand and remember. In addition, the capability of the molecular formula method to assign mean oxidation number of organic carbons for organic molecules or molecular ions is limited. To overcome these drawbacks, this article explores a new half reaction approach, the carbon-atom method, which can count the mean oxidation number of organic carbons for both organic and bioorganic compounds. The quantitative relationships among the number of transferred electrons, change in oxidation numbers of organic carbons, and mean oxidation number of organic carbons can also be established by balancing half organic reactions. Furthermore, the mean oxidation number of organic carbons for any given organic or bioorganic compounds with known structural formulas can be determined by using the carbon-atom method and the fragmentation operation.