Practice: Which of the following elements would have the lowest oxidation number?
Calculating Oxidation Numbers is the first pivotal step in understanding redox reactions.
Concept #1: Oxidation Number
Elements in Natural State have an oxidation number of zero: H2, N2, O2, F2, P4, S8, Cl2, Se8, Br2.
Example #1: Which of the following compounds would have an oxidation number or oxidation state equal to zero?
Concept #2: Ions
Oxidation number of monoatomic ions equals to their charge.
Example #2: Which of the following elements would have the most positive oxidation number based on its ionic form?
Practice: Which of the following elements would have the lowest oxidation number?
Concept #3: Oxidation Number Rules
Specific rules exist for calculating oxidation numbers of group 1A and 2A elements, F, H, O and Halogens.
Example #3: Which compound has oxygen with the lowest oxidation state?
Concept #4: Oxidation Number of Non-listed Elements
Example #4: Give the oxidation number of the carbon atom in the acetate ion: C2H3O2–
