Which of the following is Oxidation?
Hg2+ + 2e- → Zn
Zn2+ + 2e- → Zn
Fe2+ → Fe3+ + e-
MnO42- → MnO4- + e-
Fe2+ → Fe3+ + e-
MnO42- → MnO4- + e-
We know about oxidation.
Oxidation: It is a process in which an atom or a group of atoms taking part in a chemical reaction loses one of more electrons. For example:
Mg⟶ Mg2+ + 2e−
In option (c) and (d), there is loss of electrons.
Therefore, (c) and (d) are correct.