THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Atomic and mass numbers.

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.

Exposition on new concepts;
Probing questions;
Brief discussion.

text book

K.L.B.
BOOK II

PP. 1-3

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

First twenty elements of the periodic table.
Isotopes.

By the end of the lesson, the learner should be able to:
List the first twenty elements of the periodic table.
Write chemical symbols of the first twenty elements of the periodic table.
Define isotopes.
Give examples of isotopes.

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

Periodic table.

K.L.B.
BOOK II

PP. 1-3

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Electronic configuration.
Electronic configuration in diagrams.

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.
Represent electronic configuration diagrammatically.

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

Periodic table.
text book

K.L.B.
BOOK II
P. 4





PP. 5-9

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Periods 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 period.
Q/A: Examples of elements of the same period.

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

Negative ions and ion formation.
Valencies of metals.

By the end of the lesson, the learner should be able to:
To define an anion.
To describe formation of negative ions symbolically.
Recall valencies of metals among the first twenty elements in the periodic table.

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

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

Chart  ion model.
Periodic table.

K.L.B. BOOK IIP 17

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Valencie of non-metals.

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

Oxidation number.
Electronic configuration, ion formed, valency and 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.
Relate electronic configuration, ion formed, valency and oxidation number of different elements.

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

Written exercise;
Exercise review.

The periodic table.
text book

K.L.B. BOOK IIvP 18
K.L.B. BOOK IIP 18

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE

Chemical formulae of compounds. - Elements of equal valencies.

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

Discuss formation of compounds such as NaCl, MgO.

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.

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

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

text book

K.L.B. BOOK IIP 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

THE STRUCTURE OF THE ATOM & THE PERIODIC TABLE
CHEMICAL FAMILIES

Balanced chemical equations.(contd)
Alkali metals. Atomic and ionic radii of alkali metals

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





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

Supervised practice;
Written exercise.

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.

text book
The periodic

K.L.B. BOOK IIPP 25-8
K.L.B. BOOK IIPP 28-29

CHEMICAL FAMILIES

Ionisation energy of alkali metals.

By the end of the lesson, the learner should be able to:
State changes in number of energy levels and ionisation energy of alkali metals.

Examine a table of elements, number of energy levels and their ionization energy.
Discuss the trend deduced from the table.

text book

K.L.B. BOOK II

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.
Reaction of alkali metals with chlorine gas.

By the end of the lesson, the learner should be able to:
To describe reaction of alkali metals with water.
To write balanced equations for reaction of alkali metals with chlorine gas.

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.

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.

text book
Sodium, chlorine.

K.L.B. BOOK IIP. 32
K.L.B. BOOK IIP. 33

CHEMICAL FAMILIES

Compounds of alkali metals.

By the end of the lesson, the learner should be able to:
Write chemical formulae for compounds of alkali metals.
Explain formation of hydroxides, oxides and chlorides of alkali metals.

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

text book

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

Alkaline Earth metals Atomic and ionic radii 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.

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.

Some alkaline earth metals.

K.L.B. BOOK II pp 34

CHEMICAL FAMILIES

Physical properties of alkaline earth metals.

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

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 P. 35

CHEMICAL FAMILIES

Electrical properties of alkaline earth metals.

By the end of the lesson, the learner should be able to:
To describe electrical properties of alkaline earth metals.

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

Alkaline earth metals.

K.L.B. BOOK IIP. 37