Chemistry: Challenges and Solutions
Vitamin B12 (animation)
The oxidation state of an atom is the number of electrons that have either been gained or lost from its neutral state. In the center of vitamin B12 is the trace metal cobalt, which is essential for the proper functioning of the vitamin. Cobalt exists in three different oxidation states in the body: +1, +2, and +3. The amount of positive charge, or oxidation number, of the cobalt atom will determine how B12 interacts within the body.