Answer:
Fe2+ (aq) + 2e -> Fe(s)
Explanation:
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reaction:
Mg(s) + Fe2+ (aq) —>Mg2+ (aq) + Fe(s)
Magnesium loses its two valance electrons and oxidized while iron accept two electrons get reduced.
Magnesium is reducing agent while iron is oxidizing agent.
Oxidizing agents:
Oxidizing agents oxidize the other elements and itself gets reduced.
Reducing agents:
Reducing agents reduced the other element are it self gets oxidized.