1. Chapter 15 Oxidation and Reduction
15.1 Oxidation–Reduction Reactions
Learning Goal Identify what is oxidized and what is reduced in an oxidation−reduction reaction.

2. Chapter 15 Readiness
Key Math Skills
Using Positive and Negative Numbers in Calculations (1.4B)
Solving Equations (1.4D)
Core Chemistry Skills
Writing Positive and Negative Ions (6.1)
Writing Ionic Formulas (6.2, 6.4)
Balancing a Chemical Equation (8.2)
Identifying Functional Groups (8.4)

3. Oxidation and Reduction
An oxidation–reduction reaction
provides us with energy from food
provides electrical energy in batteries
occurs when iron rusts
4Fe(s) + 3O2(g)  2Fe2O3(s)

4. Oxidation and Reduction
In an oxidation–reduction reaction,
one reactant loses electrons and another reactant gains electrons
electrons are transferred from one reactant to another

5. One way to remember these definitions is to use an acronym:
Oxidized and Reduced
One way to remember these definitions is to use an acronym:
Oxidation Is a Loss of electrons (OIL)
Zn(s)  Zn2+(aq) + 2 e− (loss of electrons)
Reduction Is a Gain of electrons (RIG)
Cu2+(aq) + 2 e−  Cu(s) (gain of electrons)

6. Oxididation and Reductoin
Both metals and nonmetals undergo oxidation and reduction.

7. Oxidation−Reduction Forming Ionic Compounds
Ionic compounds are formed when
metals lose electrons to become positive ions
nonmetals gain electrons to become negative ions

8. Oxidation–Reduction Single Replacement
Every oxidation reaction is accompanied by a reduction reaction. When zinc metal is placed in a solution of copper(II) sulfate, zinc undergoes oxidation and copper undergoes reduction.

9. Oxidation−Reduction Single Replacement
Zn(s)  Zn2+(aq) + 2 e− oxidation of Zn Cu2+(aq) + 2 e−  Cu(s) reduction of Cu2+

10. Learning Check
Identify each of the following as oxidation or reduction.
Sn(s)  Sn4+(aq) e−
Fe3+(aq) + 1 e−  Fe2+(aq)
C. Cl2(g) + 2 e−  2Cl−(aq)

11. Solution
Identify each of the following as oxidation or reduction.
Sn(s)  Sn4+(aq) e− oxidation
Fe3+(aq) + 1 e−  Fe2+(aq) reduction
C. Cl2(g) + 2 e−  2Cl−(aq) reduction

12. Learning Check
Write the oxidation reaction and the reduction reaction for the following: 2Cs(s) + F2(g)  2CsF(aq)

13. Solution
Write the oxidation reaction and the reduction reaction for the following: 2Cs(s) + F2(g)  2CsF(aq) Oxidation: 2Cs(s)  2Cs+(aq) + 2 e− Reduction: F2(g) + 2 e−  2F−(aq)