by GP Bhande

2. LEARNING OUTCOMES
DEFINE A REDOX REACTION
DEFINE OXIDATION AND REDUCTION
DEFINE OXIDIZING AND REDUCING AGENTS
IDENTIFY EXAMPLES
UNDERSTAND SUCH REACTIONS IN EVERYDAY LIFE

3. WHAT IS A REDOX REACTION?
•A redox reaction is defined as any type of chemical reaction which involves the transfer
of electrons. (Sankeerthini, 2015)
•It can also be called an ‘oxidation-reduction’ reaction.
•Such reactions are always involved with two processes named: oxidation and reduction.

4. OXIDATION VS REDUCTION
OXIDATION
• OXIDATION IS THE LOSS OF ELECTRONS.
NB: ELECTRONS LOST, ARE THE ELECTRONS
GAINED!
REDUCTION
• REDUCTION IS THE GAINING OF ELECTRONS.

5. Example 1: from (kotze, 2015)

6. EXAMPLE 1 CONTINUED…
From the previous example:
•Zinc atoms lose two electrons hence, zinc undergoes oxidation (zinc is oxidised).
•Copper(II) sulphate gains the two electrons which were lost by zinc. Hence,
copper(II)sulphate undergoes reduction (it is reduced).

8. IN SIMPLE TERMS:
•An oxidizing agent is the one that causes another substance to
be reduced.
•While a reducing agent is the one that causes the other
substance to be oxidized.

9. Example 2: from (Anushika, 2014)

10. Example 2 continued …
From this example, we can conclude that:
A is oxidized(by losing electrons from B).
B is reduced (by gaining electrons from A).
A is the reducing agent, while
B is the oxidizing agent.

11. Example 3: from (wagh, 2017)

12. Example 3 continued …
From example 3: The reaction of methane with Oxygen
• methane is oxidized and is the reducing agent.
• Oxygen is reduced and is the oxidizing agent.

13. Other examples… (from sources cited above)

14. SUMMARY
For a chemical reaction to be considered as redox, electron
transfer must be evident.
Oxidation = loss of electrons = reducing agent
Reduction =gaining of electrons = oxidizing agent