Explanation:
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. An oxidation-reduction reaction is any chemical reaction in which the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. Redox reactions are common and vital to some of the basic functions of life, including photosynthesis, respiration, combustion, and corrosion or rusting.
Rules for Assigning Oxidation States
The oxidation state (OS) of an element corresponds to the number of electrons, e-, that an atom loses, gains, or appears to use when joining with other atoms in compounds. In determining the oxidation state of an atom, there are seven guidelines to follow:
The oxidation state of an individual atom is 0.
The total oxidation state of all atoms in: a neutral species is 0 and in an ion is equal to the ion charge.
Group 1 metals have an oxidation state of +1 and Group 2 an oxidation state of +2
The oxidation state of fluorine is -1 in compounds
Hydrogen generally has an oxidation state of +1 in compounds
Oxygen generally has an oxidation state of -2 in compounds
In binary metal compounds, Group 17 elements have an oxidation state of -1, Group 16 elements of -2, and Group 15 elements of -3.
