An oxidation reaction is one in which oxygen combines with an element or a compound.
Oxidation is the loss of electrons during a reaction by a molecule, atom or ion. Oxidation occurs when the oxidation state of a molecule, atom or ion is increased.
Definition
According to Classical or earlier concepts oxidation is a process that involves the addition of oxygen or any electronegative element or the removal of hydrogen or any electropositive element.
According to the electronic concept, oxidation is defined as the process in which an atom or ion loses one or more electrons.
Example
A classic example of the old definition of oxidation is when iron combines with oxygen to form iron oxide or rust. The iron is said to have oxidized into rust. The chemical reaction is:
2Fe + O2 → Fe2O3
