|MadSci Network: Chemistry|
Oxidation and Reduction is nn important part of the task of electron book-keeping. Oxidation, [O], and reduction, [R], are opposites and both must occur simultaneously, hence redox reactions. Organic chemists will normally describe a reaction as either oxidation or reduction depending on the fate of the major organic component. Oxidation: more C-O bonds (or other atoms more electronegative than C) less C-H bonds loss of electrons increased oxidation state, e.g. +1 to +3 (see below) Reduction: more C-H bonds less C-O bonds (or other atoms more electronegative than C) gain of electrons decreased oxidation state, e.g. +1 to -1 (see below) Calculating Oxidation Number or State (there are several methods for doing this, pick the one that works for you !) This allows for a more formal, quantitative decription of the oxidation state for the C atoms and is based on looking at what atoms are attached to the C atom in question. The algebraic sum of the oxidation states must equal the charge of the molecule. for attached C atoms, i.e. C-C bonds electrons shared, count 0 for attached X atoms, i.e. C-X bonds (X more electronegative), count -1 (per bond) for attached H atoms, i.e. C-H bonds (H is less electronegative than C), count +1 Add the total for atoms attached to the C in question, then switch the sign.
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