Calculating the oxidation numbers

This page provides basic exercises for calculating the oxidation numbers. When you press "New Problem", a new molecule or ion will appear. Calculate the oxidation number for the element asked, enter it in the answer cell and press "Check Answer." Results will appear in the main table. If you get a problem "incorrect", you should redo it and recheck your answer. If you miss a problem three times, pressing the "Show Answer" button will cause a complete solution to appear. Follow the rules for computing the oxidation number of an atom, ion or molecule in their order of priority.

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