THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Atomic and mass numbers.
First twenty elements of the periodic table.

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


Name the subatomic particles in an atom.
Define atomic number and mass number of an atom.
Represent atomic and mass numbers symbolically.

List the first twenty elements of the periodic table.
Write chemical symbols of the first twenty elements of the periodic table.

Exposition on new concepts;
Probing questions;
Brief discussion.
Expository approach: referring to the periodic table, teacher exposes the first twenty elements.
Writing down a list of first twenty elements of the periodic table.

text book
Periodic table.

K.L.B.
BOOK II

PP. 1-3

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Isotopes.

By the end of the lesson, the learner should be able to:
Define isotopes.
Give examples of isotopes.

Exposition of definition and examples of isotopes.
Giving examples of isotopes.

Periodic table.

K.L.B.
BOOK II
P. 4





PP. 5-8

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Electronic configuration.

By the end of the lesson, the learner should be able to:
Represent isotopes symbolically.
Define an energy level.
Describe electronic configuration in an atom.

Exposition ? teacher exposes new concepts about electronic configuration.
Written exercise.

Periodic table.

K.L.B.
BOOK II
P. 4





PP. 5-9

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Electronic configuration in diagrams.
Periods of the periodic table.

By the end of the lesson, the learner should be able to:
Represent electronic configuration diagrammatically.
Identify elements of the same period.

Supervised practice;
Written exercise.
Exposition ? Definition of a period.
Q/A: Examples of elements of the same period.

text book
Periodic table.

K.L.B.
BOOK II
PP. 5-8
K.L.B. BOOK IIP. 9

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Groups of the periodic table.

By the end of the lesson, the learner should be able to:
Identify elements of the same period.

Exposition ? definition of a group.
Q/A: examples of elements of the same group.

Periodic table.

K.L.B. BOOK IIP. 9

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Groups of the periodic table.

By the end of the lesson, the learner should be able to:
Identify elements of the same period.

Exposition ? definition of a group.
Q/A: examples of elements of the same group.

Periodic table.

K.L.B. BOOK IIP. 9

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

R.M.M. and isotopes.
Positive ions and ion formation.

By the end of the lesson, the learner should be able to:
Calculate R.M.M. from isotopic composition.

To define an ion and a cation.

Supervised practice involving calculation of RMM from isotopic composition.

Teacher gives examples of stable atoms.
Guided discovery that metals need to lose one, two or three electrons to attain stability.
Examples of positive ions.

text book

K.L.B. BOOK IIPP. 11-13
K.L.B. BOOK IIPP 14-15

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Positive ions representation.

By the end of the lesson, the learner should be able to:
To represent formation of positive ions symbolically.

Diagrammatic representation of cations.

Chart  ion model.

K.L.B. BOOK IIP 16

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Negative ions and ion formation.

By the end of the lesson, the learner should be able to:
To define an anion.
To describe formation of negative ions symbolically.

Teacher gives examples of stable atoms.
Guided discovery of formation of negative ions.
Diagrammatic representation of anions.

Chart  ion model.

K.L.B. BOOK IIP 17

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Valencies of metals.
Valencie of non-metals.

By the end of the lesson, the learner should be able to:
Recall valencies of metals among the first twenty elements in the periodic table.
Recall valencies of non-metals among the first twenty elements in the periodic table.

Q/A to review previous lesson;
Exposition;
Guided discovery.

Periodic table.

K.L.B. BOOK IIP 17

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Valencies of radicals.

By the end of the lesson, the learner should be able to:
Define a radical.
Recall the valencies of common radicals.

Exposition ? teacher defines a radical, gives examples of radicals and exposes their valencies.
Students draw a table of radicals and their valencies.

text book

K.L.B. BOOK IIP 18

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Oxidation number.

By the end of the lesson, the learner should be able to:
Define oxidation number.
Predict oxidation numbers from position of elements in the periodic table.

Q/A: Valencies.
Expose oxidation numbers of common ions.
Students complete a table of ions and their oxidation numbers.

The periodic table.

K.L.B. BOOK IIvP 18

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Electronic configuration, ion formed, valency and oxidation number
Chemical formulae of compounds. - Elements of equal valencies.

By the end of the lesson, the learner should be able to:
Relate electronic configuration, ion formed, valency and oxidation number of different elements.
To derive the formulae of some compounds involving elements of equal valencies.

Written exercise;
Exercise review.
Discuss formation of compounds such as NaCl, MgO.

text book

K.L.B. BOOK IIP 18
K.L.B. BOOK IIPP 19-20

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Chemical formulae of compounds. -Elements of unequal valencies.

By the end of the lesson, the learner should be able to:
To derive the formulae of some compounds involving elements of unequal valencies.

Discuss formation of compounds such as MgCl2
Al (NO3)3

text book

K.L.B. BOOK IIPP 19-20

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Chemical formulae of compounds. -Elements of unequal valencies.

By the end of the lesson, the learner should be able to:
To derive the formulae of some compounds involving elements of unequal valencies.

Discuss formation of compounds such as MgCl2
Al (NO3)3

text book

K.L.B. BOOK IIPP 19-20

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Chemical formulae of compounds. -Elements of variable valencies.
Chemical equations.

By the end of the lesson, the learner should be able to:
To derive the formulae of some compounds involving elements of variable valencies.
To identify components of chemical equations.

Discuss formation of compounds such as
-Copper (I) Oxide.
-Copper (II) Oxide.
-Iron (II) Sulphate.
-Iron (III) Sulphate.

Review word equations;
Exposition of new concepts with probing questions;
Brief discussion.

text book

K.L.B. BOOK IIP 20
K.L.B. BOOK IIPP 21-23

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Balanced chemical equations.

By the end of the lesson, the learner should be able to:
To balance chemical equations correctly.

Exposition;
Supervised practice.

text book

K.L.B. BOOK IIPP 24-25

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Balanced chemical equations.(contd)

By the end of the lesson, the learner should be able to:
To balance chemical equations correctly.

Supervised practice;
Written exercise.

text book

K.L.B. BOOK IIPP 25-8

CHEMICAL FAMILIES

Alkali metals. Atomic and ionic radii of alkali metals
Ionisation energy of alkali metals.

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





Identify alkali metals.
State changes in atomic and ionic radii of alkali metals.

State changes in number of energy levels and ionisation energy of alkali metals.

Q/A to reviews elements of group I and their electronic configuration.
Examine a table of elements, their symbols and atomic & ionic radii.
Discussion & making deductions from the table.
Examine a table of elements, number of energy levels and their ionization energy.
Discuss the trend deduced from the table.

The periodic
text book

K.L.B. BOOK IIPP 28-29

CHEMICAL FAMILIES

Physical properties of alkali metals.

By the end of the lesson, the learner should be able to:
State and explain trends in physical properties of alkali metals.

Examine a table showing comparative physical properties of Li, Na, and K.
Q/A: Teacher asks probing questions as students refer to the table for answers.
Detailed discussion on physical properties of alkali metals.

Chart ? comparative properties of Li, Na, K.

K.L.B. BOOK IIPP 30-31

CHEMICAL FAMILIES

Chemical properties of alkali metals.

By the end of the lesson, the learner should be able to:
To describe reaction of alkali metals with water.

Q/A: Review reaction of metals with water.
Writing down chemical equations for the reactions.
Deduce and discuss the order of reactivity down the group.

text book

K.L.B. BOOK IIP. 32

CHEMICAL FAMILIES

Reaction of alkali metals with chlorine gas.
Compounds of alkali metals.

By the end of the lesson, the learner should be able to:
To write balanced equations for reaction of alkali metals with chlorine gas.
Write chemical formulae for compounds of alkali metals.
Explain formation of hydroxides, oxides and chlorides of alkali metals.

Teacher demonstration- reaction of sodium with chlorine in a fume chamber.
Q/A: Students to predict a similar reaction between potassium and chlorine.
Word and balanced chemical equations for various reactions.


Exercise: Completing a table of hydroxides, oxides and chlorides of alkali metals.
Discuss combination of ions of alkali metals with anions.

Sodium, chlorine.
text book

K.L.B. BOOK IIP. 33
K.L.B. BOOK II pp 33

CHEMICAL FAMILIES

Uses of alkali metals.

By the end of the lesson, the learner should be able to:
State uses of alkali metals.

Descriptive approach: Teacher elucidates uses of alkali metals.

text book

K.L.B. BOOK II pp 34

CHEMICAL FAMILIES

Uses of alkali metals.

By the end of the lesson, the learner should be able to:
State uses of alkali metals.

Descriptive approach: Teacher elucidates uses of alkali metals.

text book

K.L.B. BOOK II pp 34

CHEMICAL FAMILIES

Alkaline Earth metals Atomic and ionic radii of alkaline earth metals.
Physical properties of alkaline earth metals.

By the end of the lesson, the learner should be able to:
Identify alkaline earth metals.

State changes in atomic and ionic radii of alkaline earth metals.
State and explain trends in physical properties of alkaline earth metals.

Q/A: Elements of group I and their electron configuration.
Examine a table of elements, their symbols and atomic & ionic radii.
Make deductions from the table.

Examine a table showing comparative physical properties of Be, Mg, Ca.
Q/A: Teacher asks probing questions as students refer to the table for answers.
Detailed discussion of physical properties of alkaline earth metals.

Some alkaline earth metals.

K.L.B. BOOK II pp 34
K.L.B. BOOK II P. 35

CHEMICAL FAMILIES
STRUCTURE & BONDING

Electrical properties of alkaline earth metals.
Chemical bonds. Ionic bond.

By the end of the lesson, the learner should be able to:
To describe electrical properties of alkaline earth metals.
Describe role of valence electrons in determining chemical bonding.
Explain formation of ionic bonding.

Teacher demonstration: -
To show alkaline metals are good conductors of electric charge.
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.

Alkaline earth metals.
text book

K.L.B. BOOK IIP. 37

STRUCTURE & BONDING

Ionic bond representation.
Grant ionic structures.

By the end of the lesson, the learner should be able to:
Use dot and cross diagrams to represent ionic bonding.
Describe the crystalline ionic compound.
Give examples of ionic substances.

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

Chart- dot and cross diagrams.
Models for bonding.
Giant sodium chloride model.

K.L.B. BOOK II P. 58

STRUCTURE & BONDING

Physical properties of ionic compounds.
Covalent bond.
Co-ordinate bond.
Molecular structure.

By the end of the lesson, the learner should be able to:
Describe physical properties of ionic compounds.
Explain the differences in the physical properties of ionic compounds.
Explain the formation of covalent bond
Use dot and cross diagrams to represent covalent bond.
To describe the co-ordinate bond
To represent co-ordinate bond diagrammatically.
To describe the molecular structure.
To give examples of substance exhibiting molecular structure

Analyse tabulated comparative physical properties of ionic compounds.
Teacher asks probing questions.
Exposition: Shared pair of electrons in a hydrogen molecule, H2O, NH3, Cl2, and CO2.
Drawing of dot-and-cross diagrams of covalent bonds.
Exposition- teacher explains the nature of co-ordinate bond.
Students represent co-ordinate bond diagrammatically.
Discussion ? To explain formation of the giant structure and give examples of substance exhibiting molecular structure.

text book

K.L.B. BOOK IIPP 58-59
K.L.B. BOOK II P 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.
To describe giant atomic structure in diamond.
To state uses of diamond.

Discuss comparative physical properties of substances. exhibiting molecular structure.
Explain variation in the physical properties.
Diagrammatic representation of diamond.
Discuss uses of diamond.

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.
To describe mutual electronic forces between electrons and nuclei.
To describe metallic bond.
To compare physical properties of metals.
To state uses of some metals.

Diagrammatic representation of graphite.
Discuss uses of graphite.
Discussion:
Detailed analysis of comparative physical properties of metals and their uses.
Probing questions & brief explanations.

Diagrams in textbooks.
text book

K.L.B. BOOK II pp 69