Rusting is a redox reaction. Redox reactions involve the transfer of electrons between reacting species, resulting in one species being oxidized while the other is reduced. In rusting, iron is oxidized by oxygen in the air, forming iron oxide. The iron loses electrons and is oxidized, while the oxygen gains electrons and is reduced.

1. 1
RUSTING IS A REDOX
REACTION
• DEFINITIONS FOR OXIDATION AND REDUCTION
• OXIDISING AND REDUCING AGENTS
• OXIDATION NUMBER
• NAMING OF COMPOUNDS USING IUPAC NOMENCLATURE
NAME………………………………………………CLASS………..TEACHER……

2. 2
QUESTION 1
What is meant by REDOX reaction?
……………………………………………………………………………………..
………………………………………………………………………………………
QUESTION 2
What is meant by oxidation and reduction?
Oxidation and reduction could be defined from 4 different angles . Fill in the table below
Oxidation reaction Reduction Reaction
a) Oxygen gain or
oxygen loss
b) Hydrogen gain or
hydrogen loss
c) electron transfer
d) changes in oxidation
number
QUESTION 3. Choose the best answer for statements below
A) Definition of REDOX involving oxygen gain or oxygen loss
2Mg + CO2  2MgO + C
i) Magnesium undergoes oxidation/reduction reaction because
magnesium has gain/lost oxygen
ii) Carbon undergoes oxidation/reduction reaction because carbon
has gain/lost oxygen

3. 3
B) Definition of REDOX involving hydrogen gain or hydrogen loss
H2S + F2  S + 2HF
i) Sulphur undergoes oxidation/reduction reaction because
Sulphur has gain/lost hydrogen
ii) Fluorine undergoes oxidation/reduction reaction because fluorine
has gain/lost hydrogen
C) Definition of REDOX involving electron transfer.
First complete the ion-electron equation below
And then identify whether the equations are oxidation or reduction reactions
Ion-electron equations Oxidation or Reduction
reactions?
1 example
Mg 2+ +2e  Mg
2
2O 2-  O2
3
Cl 2  2Cl -
4
2H +  H2
5
Zn  Zn 2+
6
2Cl -  Cl2
D) Definition of REDOX involving changes in oxidation number .
a) What is meant by OXIDATION NUMBER?
………………………………………………………………….

4. 4
b) Calculate OXIDATION NUMBER for the underlined below
1 K2Cr2O7 6 MnO4 -
2 SO2 7 FeCl3
3 Mg 8 H2
4 MgSO4 9 Br2
5 10
NO3 – K2SO4
c) Identify the reactions below whether they are oxidation reactions or
reduction reactions by calculating the changes in OXIDATION NUMBER
Reactions Changes in Oxidation reaction /
oxidation number reduction reaction or
neither?
1
Cu 2+  Cu
2 Br2  2Br-
3 MnO2-  Mn 2+
4 IO3 -  I2
5 CrO4 2-  Cr2O7 2-
QUESTION 4

5. 5
State whether the following reactions are oxidation reactions or reduction
reactions based on the 4 definitions of redox reactions
Redox reactions Oxidation reaction / Give reasons for your
reduction reaction ? answers
1 Mg  MgO
2 CO2 C
3 H2S S
4 Cl2  HCl
5 NH3  N2
6 CuO  Cu
7 Cu 2+ + 2e  Cu
8 MnO 4 -  Mn 2+
9 2I -  I2
10 FeCl3  FeCl2

6. 6
A) NAMING OF CATIONS USING IUPAC NOMENCLATURE
Name compounds below using IUPAC nomenclature
Element formulae Name
a) Chromium Cr2O3
b) Copper Cu2O
c) Manganese KMnO4
d) CuO
e) PbO2
e) FeCl3
f) Zinc Zn(NO3)2
B) NAMING OF ANIONS USING IUPAC NOMENCLATURE
Name compounds below using IUPAC nomenclature
elements Formulae Name
a) Bromine NaBr
b) Na3PO4
d) NaClO4
e) Chlorine and NaClO
oxygen
f) KNO3
g) NaS

7. 7
Oxidized reduced
Choose the best words in the box above to fill in the blanks below
a) AN OXIDIZING AGENT ……………………………………a substance
b) It is ……………………………….in a redox reaction
c) A REDUCING AGENT …………………….. a substance.
d) It is ……………………..in a redox reaction
2FeO + C  2Fe + CO2
Choose the best words in the box above to fill in the blanks below
Oxidized reduced Oxidising Reducing
a) FeO is the ……………………. agent for this reaction.
b) It ………………………carbon into carbon dioxide
c) In the process, FeO itself is ………………………….to Fe
d) C is the ………………………. agent for this reaction.
e) C ………………………FeO into Fe
f) In the process, C itself is ………………………….to CO2