Review of Oxidation and Reduction Oxidation is the loss of electrons or H atoms. A reducing agent is one that looses electrons.
Reduction is the gain of electrons or H atoms.
An oxidizing agent is one that gains electrons. Oxidation and reduction are paired reactions. The oxidation state of a carbon atom depends on the other atoms to which it is bonded. As organic molecules are oxidized, the transfer of electrons and hydrogen atoms provides free energy. Glycolysis - cytoplasm 2.