STRUCTURE & BONDING

Chemical bonds. Ionic bond.

By the end of the lesson, the learner should be able to:
Describe role of valence electrons in determining chemical bonding.


Explain formation of ionic bonding.

Q/A: Review valence electrons of atoms of elements in groups I, II, III, VII and VIII.
Q/A: Review group I and group VII elements.
Discuss formation of ionic bond.

text book

K.L.B. BOOK IIP54




PP 57-58

STRUCTURE & BONDING

Ionic bond representation.

By the end of the lesson, the learner should be able to:
Use dot and cross diagrams to represent ionic bonding.

Drawing diagrams of ionic bonds.

Chart- dot and cross diagrams.
Models for bonding.

K.L.B. BOOK II P. 58

STRUCTURE & BONDING

Grant ionic structures.
Physical properties of ionic compounds.

By the end of the lesson, the learner should be able to:
Describe the crystalline ionic compound.
Give examples of ionic substances.

Discuss the group ionic structures of NaCl.
Teacher gives examples of other ionic substances: KNO3, potassium bromide, Ca (NO3)2, sodium iodide.

Giant sodium chloride model.
text book

K.L.B. BOOK II PP 56-58

STRUCTURE & BONDING

Covalent bond.
Co-ordinate bond.
Molecular structure.

By the end of the lesson, the learner should be able to:
Explain the formation of covalent bond
Use dot and cross diagrams to represent covalent bond.
To describe the molecular structure.
To give examples of substance exhibiting molecular structure

Exposition: Shared pair of electrons in a hydrogen molecule, H2O, NH3, Cl2, and CO2.
Drawing of dot-and-cross diagrams of covalent bonds.

Discussion ? To explain formation of the giant structure and give examples of substance exhibiting molecular structure.

text book

K.L.B. BOOK II PP 60-63
K.L.B. BOOK IIP 65

STRUCTURE & BONDING

Trend in physical properties of molecular structures.
Giant atomic structure in diamond.

By the end of the lesson, the learner should be able to:
To describe van- der -waals forces.
To explain the trend in physical properties of molecular structures.

Discuss comparative physical properties of substances. exhibiting molecular structure.
Explain variation in the physical properties.

Sugar, naphthalene, iodine rhombic sulphur.
Diagrams in textbooks.

K.L.B. BOOK IIP 65

STRUCTURE & BONDING

Giant atomic structure in graphite.
Metallic bond. Uses of some metals.

By the end of the lesson, the learner should be able to:
To describe giant atomic structure in graphite.
To state uses of graphite.

Diagrammatic representation of graphite.

Discuss uses of graphite.

Diagrams in textbooks.
text book

K.L.B. BOOK II pp 69

EFFECTS OF AN ELECTRIC CURRENT ON SUBSTANCES.

Molten electrolytes.

By the end of the lesson, the learner should be able to:
To test for electrical conductivities molten electrolytes.

Group experiments- to identify electrolytes in molten form.
Explain the difference in molten electrolytes.

Molten candle wax
Sugar
Sulphur
Lead oxide.

K.L.B. BOOK IIPP. 120-121

EFFECTS OF AN ELECTRIC CURRENT ON SUBSTANCES.

Electrolysis.
Aqueous electrolytes. Electrodes.
Reaction on electrodes.

By the end of the lesson, the learner should be able to:
To define electrolysis
To describe the process of electrolysis in terms of charge movement.
To describe half- equation reactions at the cathode and anode

Descriptive approach punctuated with Q/A.
To demonstrate ?Electrolysis of molten lead (II) bromide
Observe colour changes
Explanation of half-equations and reactions at the electrodes.

Graphite electrodes
Battery
Various aqueous solutions switch bulb.
Graphite electrodes
Battery
Various aqueous solutions switch.

K.L.B. BOOK II
K.L.B. BOOK II PP.126-127

EFFECTS OF AN ELECTRIC CURRENT ON SUBSTANCES.

Binary electrolyte.

By the end of the lesson, the learner should be able to:
To define a binary electrolyte.
To state the products of a binary electrolyte.

Completing a table of electrolysis of binary electrolytes.

text book

K.L.B. BOOK II P.127

EFFECTS OF AN ELECTRIC CURRENT ON SUBSTANCES.

Application of electrolysis.
Electroplating.

By the end of the lesson, the learner should be able to:
To state application of electrolysis.

Discussion and explanations.

text book
Silver nitrate
Iron nail
Complete circuit battery.

K.L.B. BOOK II P. 128

CARBON AND SOME OF ITS COMPOUNDS.

Allotropy.
Physical and chemical properties of diamond, graphite and amorphous carbon

By the end of the lesson, the learner should be able to:
Define allotropes and allotropy.
Identify allotropes of carbon.
Represent diamond and graphite diagrammatically.

Teacher exposes new terms.
Review covalent bond.
Discuss boding in diamond and graphite.

text book
Charcoal, graphite.

K.L.B. BOOK II PP. 131-133

CARBON AND SOME OF ITS COMPOUNDS.

Burning carbon and oxygen.
Reduction properties of carbon.
Reaction of carbon with acids. Preparation of CO2.

By the end of the lesson, the learner should be able to:
Describe reaction of carbon with oxygen.
Describe reduction properties of carbon.
Show reduction properties of carbon.

Teacher demonstration- Prepare oxygen and pass dry oxygen into a tube containing carbon. Heat the carbon. Observe effects on limewater.
Teacher demonstration ? Burn strongly a mixture of carbon and CuO on a bottle top.
Observe colour changes and give underlying explanation

Carbon, limewater, tube, limewater stand& Bunsen burner.
CuO, pounded charcoal, Bunsen burner& bottle top
Conc. HNO3, limewater.

K.L.B. BOOK II PP. 134-135
K.L.B. BOOK II P.126

CARBON AND SOME OF ITS COMPOUNDS.

Properties of CO2.

By the end of the lesson, the learner should be able to:
Describe properties of CO2

Simple experiments to determine properties of CO2.

Discuss the observations.

Lime water,
Magnesium ribbon,
Universal indicator,
lit candle.

K.L.B. BOOK II PP.138-139

CARBON AND SOME OF ITS COMPOUNDS.

Chemical equations for reactions involving CO2.

By the end of the lesson, the learner should be able to:
Write balanced CO2.

Give examples of reactions. Write corresponding balanced chemical equations.

text book

K.L.B. BOOK II PP.139-140

CARBON AND SOME OF ITS COMPOUNDS.

Uses of CO2.
Carbon monoxide lab preparation.

By the end of the lesson, the learner should be able to:
State uses of CO2

Discuss briefly the uses of CO2.

text book

K.L.B. BOOK II PP.140-1

CARBON AND SOME OF ITS COMPOUNDS.

Chemical properties of carbon monoxide.
Carbonates and hydrogen carbonates.
Heating carbonates and hydrogen carbonates.
Extraction of sodium carbonate from trona.

By the end of the lesson, the learner should be able to:
To describe chemical properties of carbon monoxide.
To write equations for reaction of carbonates and hydrogen carbonates on heating.

Description of properties of carbon monoxide.
Discussion and writing of chemical equations.
Discuss the above observations.
Write corresponding balanced equations.

text book

K.L.B. BOOK II PP. 144-145
K.L.B. BOOK II PP.150-151

CARBON AND SOME OF ITS COMPOUNDS.

Solvay process of preparing sodium carbonate.

By the end of the lesson, the learner should be able to:
To draw schematic diagram for extraction of sodium carbonates.

Discuss each step of the process.

Write relevant equations.

text book, chart

K.L.B. BOOK II

CARBON AND SOME OF ITS COMPOUNDS.

Importance of carbon in nature. & its effects on the environment.

By the end of the lesson, the learner should be able to:
To discuss: - Importance of carbon in nature.
&
Effects of carbon on the environment.

Discuss the carbon cycle and processes that increase/ reduce amount of CO2 in the air.
Uses of CO2 in soft drinks and fire extinguishers.

text book

K.L.B. BOOK II PP.157-158