THE MOLE

Mole, molar mass and R.A.M.
Number of moles in a substance.
Relative molecular mass & Relative formula mass.

By the end of the lesson, the learner should be able to:
Define the term mole as a quantity of measurement.
Relate the mole to R.A.M and molar mass.
Calculate number of moles in a given mass of a substance.
Define relative molecular mass.
Calculate RMM of a compound.

Discuss various analogies that lead to the definition of the mole.
Expose the meaning of R.A.M., Avogadro?s constant and molar mass.
Worked examples.
Supervised practice.
Q/A: - Review formulae of compounds.
Complete a table of compounds and their molecular / formula mass.

Chart- table of molar masses of elements.
student book
Calculators.

K.L.B. BK III
PP. 27-31
Longhorn
Book III
PP 34-35

K.L.B.BK III
PP. 34-35

Longhorn Book III PP 44-60

THE MOLE

Moles and Avogadro?s number.

By the end of the lesson, the learner should be able to:
Calculate number of particles in a given number of moles.

Review standard form of numbers.
Worked examples.
Supervised exercise.

Calculators.

K.L.B.BK III
PP. 3132
Longhorn
Book III
PP 30-31

THE MOLE

Empirical Formula.

By the end of the lesson, the learner should be able to:
Determine empirical formula of a compound given percentage composition by mass.

Worked examples.
Supervised practice.

Assignment.

student book

K.L.B.
BK III P. 43

Longhorn Book III PP 66-71

THE MOLE

Molecular formula.

By the end of the lesson, the learner should be able to:
Define molecular formula of a compound.
Find molecular formula given percentage composition of a compound by mass.

Worked examples.

Supervised practice.

Calculators.

K.L.B.BK III
P. 45

Longhorn
Book III
PP 73-75

THE MOLE

Concentration of a solution.
Molarity of a solution.
Preparation of molar solutions.
Calculators on molar solutions.

By the end of the lesson, the learner should be able to:
Define concentration of a solution.
Find concentration of a solution in grams/litre and moles/litre.
Define molarity of a solution.
Find molarity of a solution in M/dm?
Define molar solutions.
Prepare molar solutions.
Solve numerical calculations on molar solutions.
Problems on molar solutions.

Q/A: - Equivalent ratios, e.g. 4g dissolved in 500cm? and
8g in 1 litre.
Worked examples on concentration of solutions.
Teacher explains that molarity of a solution is given in moles of the solute per litre.
Worked examples.
Supervised exercise.
Q/A: - Description of preparation of molar solutions.
Worked examples.
Supervised exercise.
Assignment.

chart
student book
Volumetric flasks, teat droppers/wash bottle.
Sodium hydrogen pellets.
Weighing balance.
student book

K.L.B. BK III
PP. 46-48

Longhorn Book III PP 76-81

K.L.B. BK III
PP. 50-51

Longhorn
Book III
PP 78-81

THE MOLE

Dilution of solutions.

By the end of the lesson, the learner should be able to:
Calculate molarity of a solution after dilution.

Group experiments.
Calculations.

student book

K.L.B. BK III
PP. 76-81

THE MOLE

Stoichiometry of a chemical reaction.
Stoichiometric equations.

By the end of the lesson, the learner should be able to:
To determine mole ratio of given reactions.
To define a stoichiometric equation.

Group experiments: - Determine masses, hence moles of reacting CuSO4 solution and iron metal.
To write stoichiometric equations of the above reactions.

CuSO4 solution and iron metal.
student book

K.L.B. BK III
P. 56
Longhorn Book III PP 87-92

THE MOLE

Stoichiometric equations of various reactions.

By the end of the lesson, the learner should be able to:
To investigate and determine Stoichiometric equations of various reactions.

Class experiments.

Problem solving.

student book

K.L.B. BK III
P. 62

Volumetric Analysis.

Apparatus used in titration experiments.
Titration process.

By the end of the lesson, the learner should be able to:
To use and read a pipette and a burette.
To define titration as a process.
Define a titration end-point.

Discussion and practical use of the apparatus.
Emphasis is laid on need to sterilize the apparatus after use.

Review by Q/A: -
-Indicators and colour changes.
-Choice of indicators.
-Balanced chemical equations.
Discuss characteristics of a good titre, when an an-end point is attained.

Pipettes
Burettes.
Indicators
Suitable acid and base.

K.L.B. BK III
PP. 63-64
Longhorn
Book III
PP 104-8

K.L.B.
BK III
PP. 64-67

Longhorn
Book III
PP 108-114

Volumetric Analysis.

Titration experiment (Neutralization reaction)

By the end of the lesson, the learner should be able to:
To carry out a titration experiment and obtain accurate results.

Class experiments: - To neutralize HCl with NaOH solution.
Fill in a table of results.
Find the average base used.

student book

K.L.B. BK III
P. 66

Longhorn Book III PP 108-114

Volumetric Analysis.

Titration experiment (Neutralization reaction)
Basicity of an acid.

By the end of the lesson, the learner should be able to:
To carry out calculations from experimental results.
To define basicity of an acid.

Step-by-step calculations.
Complete a table of number of replaceable hydrogen ions of an acid; hence define basicity of an acid.
Write corresponding ionic equations.

Calculators.
student book

K.L.B. BK III
P 66
Longhorn Book III PP 108-114

Volumetric Analysis.

Standardization of HCl.

By the end of the lesson, the learner should be able to:
To define standardization of HCl.

Class experiments.

Dilute HCl, Na2CO3 solutions.

K.L.B. BK III
PP. 74-75

Volumetric Analysis.

Concentration of HCl.
Redox Titration Reactions.
Water of crystallization.

By the end of the lesson, the learner should be able to:
To calculate concentration of HCl from experimental results.
To standardize a solution with an iron (II) salt.
To determine amount of water of crystallization in ammonium iron sulphate crystals.

Calculations & supervised practice.
Experiment and calculations.
Teacher exposes the formula of water of crystallization.
Class experiment.
Filling in a table of results.

Potassium Magnate
(VII)
Ammonium
Iron (II)
Sulphate crystals.
Dilute sulphuric (VI) acid.

K.L.B. BK III
PP. 74-75
K.L.B. BK III
PP. 74-75

Longhorn
Book III
PP 114-115

Volumetric Analysis.

Formula mass of ammonium iron (II) sulphate.

By the end of the lesson, the learner should be able to:
To find formula mass of ammonium iron (II) sulphate.

Calculations from experimental results.

student book

K.L.B. BK III
PP. 76 -77

Volumetric Analysis.

Formula mass of a given salt.
Atomicity of gases.

By the end of the lesson, the learner should be able to:
To solve numerical problems involving water of crystallization.
To define atomicity of gases.

Problem solving from sample results.
Review by Q/A atoms and molecules; hence the definition.
Discuss a table of gases and their atomicity.

student book

K.L.B. BK III
P.77

Volumetric Analysis.

Mass and volume of gases.

By the end of the lesson, the learner should be able to:
To determine mass and volume of gases.

Teacher demonstration: - Determining mass of known volumes of oxygen / CO2.

Lubricated syringes
Oxygen/
CO2.

K.L.B. BK III
P. 81
Longhorn BK III
PP 126-127

Volumetric Analysis.

Molar gas volume.
Combining volumes of gases.
Gay Lussac?s Law.

By the end of the lesson, the learner should be able to:
To define molar gas volume.
To compare combining volumes of two reacting gases.
To state Gay Lussac?s Law.
To compare Gay Lussac?s Law with Avogadro?s Law.
To solve numericals using Gay Lussac?s Law.

Use the above results to describe volume of one mole of a gas.
Discuss molar gas volume at R.T.P and S.T.P conditions.
Teacher demonstration: - Determining volumes of reacting gases; hence deduce volume rations.
Teacher exposes the law; and compares it with Gay Lussac?s Law.
Worked examples.
Supervised practice.

student book

K.L.B. BK III
79 ? 80
Longhorn
Book III
PP 126-127

K.L.B. BK III
P. 85

Longhorn
Book III
PP 129-131

ACIDS, BASES AND SALTS.

Strength of acids. Acids in aqueous form.

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


Define an acid in terms of hydrogen ions.

Explain strength of acids in aqueous form in terms of number of hydrogen ions present.

Class experiments: investigate reactions of magnesium and zinc carbonate with different acids.
Make and record observations in tabular form.
Make deductions from the observations.
Write relevant chemical equations and ionic equations.
Detailed discussion leading to the definition of an acid and explanation of strength of an acid.

Magnesium strip, zinc carbonate,
2M HCl,
2M H2SO4,
2M ethanoic acid.

K.L.B. BK IV
Pages 1-4

ACIDS, BASES AND SALTS.

Strength of acids. Acids in aqueous form.

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


Define an acid in terms of hydrogen ions.

Explain strength of acids in aqueous form in terms of number of hydrogen ions present.

Class experiments: investigate reactions of magnesium and zinc carbonate with different acids.
Make and record observations in tabular form.
Make deductions from the observations.
Write relevant chemical equations and ionic equations.
Detailed discussion leading to the definition of an acid and explanation of strength of an acid.

Magnesium strip, zinc carbonate,
2M HCl,
2M H2SO4,
2M ethanoic acid.

K.L.B. BK IV
Pages 1-4

ACIDS, BASES AND SALTS.

pH values of acids. Electrical conductivities of aqueous acids.

By the end of the lesson, the learner should be able to:
Determine strength of acids using pH values.

Determine strengths of acids by comparing their electrical conductivities.

Classify acids as either strong or weak in terms of partial dissociations in aqueous solutions.

Q/A: review determination of strength of acids using a litmus paper and pH scale.
Class / group experiments: record colour of universal indicator in
2M HCl and 2M ethanoic acid.
Set up voltameters of 2M HCl and 2M ethanoic acid in turns.
Record amounts of current .
Discuss the observations.
Write corresponding ionic equations.

Universal
indicator,
2M HCl,
2M ethanoic acid,
dry cells,
carbon electrodes,
milli-ammeters,
wires, switches etc.

K.L.B. BK IV
Pages 4-6

ACIDS, BASES AND SALTS.

Definition of a base in terms of hydroxide ions.
Neutralization reaction.
Strength of bases.

By the end of the lesson, the learner should be able to:
Define a base in terms of hydroxide ions.
Determine the results of reaction of an acid and a base.
Compare strengths of bases using pH values and electrical conductivity.


Classify bases/ alkali as either strong or weak in terms of complete / partial ionization.

Teacher demonstration:
Dissolve calcium hydroxide in water.
Carry out litmus test on the resulting solution.
Discuss the results; hence define a base in terms of hydroxide ions.
Add 1M HCl to an aqueous solution of Calcium hydroxide drop wise until colour, change of the universal indicator is noted.
Write ionic equation for the reaction.
Carry out pH tests of 2M NaOH and 2M ammonia solution using universal indicator solutions; and observe colour changes.

Carry out electrical conductivity tests of voltameters of the above solutions.

Discussion: relate number of hydroxide ions to pH values and electrical conductivity of bases.

Red litmus paper, calcium hydroxide solid.
1M HCl,
Calcium hydroxide,
universal indicator.
2M NaOH,
2M ammonia solution, universal indicator solutions, dry cells,
carbon electrodes,
milliammeters,
wires, switches etc

K.L.B. BK IV
Pages 6-7
K.L.B. BK IV
Pages 7-9

ACIDS, BASES AND SALTS.

Dissolving hydrogen chloride gas in water / methylbenzene.

By the end of the lesson, the learner should be able to:
Define a polar and a non-polar solvent.

Teacher demonstration:
Dissolving HCl gas in different solvents.
Discuss the observations.
Write down related balanced chemical equations.

Ammonia gas,
Methylbenzene, hydrogen chloride gas.

K.L.B. BK IV
Pages 9-11

ACIDS, BASES AND SALTS.

Dissolving ammonia gas in water/ methylbenzene.

By the end of the lesson, the learner should be able to:
Investigate effect of a polar / non-polar solvent on ammonia gas.

Carry out litmus tests on the resulting solution.
Make observations and deductions thereof.
Write down related balanced chemical equations.

Ammonia gas,
Methylbenzene.

K.L.B. BK IV
Pages 11-12

ACIDS, BASES AND SALTS.

Amphoteric oxides.

By the end of the lesson, the learner should be able to:
Define an amphoteric oxide.
Identify some amphoteric oxides.

Class experiment:
Carry out acid / base reactions with metal oxides.
Q/A: make deductions from the results.
Writing and balancing relevant equations.

2M Nitric acid
2M NaOH,
HNO3.
Amphoteric oxides.

K.L.B. BK IV
Pages 12-14

ACIDS, BASES AND SALTS.

Precipitation Reactions.
Solubility of chlorides sulphites and sulphates.
Equations for formation of insoluble chlorides, sulphites and sulphates.

By the end of the lesson, the learner should be able to:
Define a precipitate.
Write ionic equations showing formation of precipitates.

Find out cations that form (in)soluble chlorides, sulphates and sulphites.
Write down equations for formation of insoluble chlorides, sulphites and sulphates.

Q/A: review definition of a salt.
Class experiment;
Add sodium carbonate or a suitable carbonate to various salt solutions containing Mg2+, Al3+, Ca2+, etc.
Make observations and discuss the results.


Class experiments: measure 2cc of 0.1M solution containing Pb2+ into a test tube.
Add drops of 2M NaCl solution.
(Later 2M Sodium Sulphate and 2M Sodium Sulphate).
Warm the mixture and make observations.
Repeat the procedure using other salt solutions containing other ions.
Tabulate the results.
Q/A: review observations made in the above experiments.
Discuss the solubility of the cations.
Write relevant ionic equations.

Soluble carbonates e.g. Na2CO3, K2CO3, (NH4)2CO3
Salt solutions containing Mg2+, Al3+, Ca2+, etc.

0.1M solution containing Pb2+, 2M NaCl solution, 2M sodium sulphate, source of heating.
student book

K.L.B. BK IV
Pages 14-16
K.L.B. BK IV
Pages 16-17

ACIDS, BASES AND SALTS.

Complex ions.

By the end of the lesson, the learner should be able to:
Explain formation of complex ions.

Add drops of 2M sodium hydroxide / 2M ammonia solution to a solution containing Mg2+, Zn2+, etc.

Make observations and discuss the results.

2M Sodium hydroxide (2M ammonia solution),
solution containing Mg2+, Zn2+, etc.

K.L.B. BK IV
Pages 18-20

ACIDS, BASES AND SALTS.

Complex ions.

By the end of the lesson, the learner should be able to:
Explain formation of complex ions.

Add drops of 2M sodium hydroxide / 2M ammonia solution to a solution containing Mg2+, Zn2+, etc.

Make observations and discuss the results.

2M Sodium hydroxide (2M ammonia solution),
solution containing Mg2+, Zn2+, etc.

K.L.B. BK IV
Pages 18-20

ACIDS, BASES AND SALTS.

Solubility of a salt at a given temperature.

By the end of the lesson, the learner should be able to:
Define the term solubility.
Determine solubility of a given salt at room temperature.

Q/A: review the terms saturated, unsaturated solutions & crystallization.
Class experiment: determine mass of a solute that dissolves in 100cc of water at room temperature.

Suitable solutes.

K.L.B. BK IV
Pages 20-21

ACIDS, BASES AND SALTS.

Problems solving on solubility.
Effect of temperature on solubility of a solute in a solvent.
Effects of various salts on soap.

By the end of the lesson, the learner should be able to:
Solve problems involving solubility of a solute in a solvent at a given temperature.
Investigate the effect of temperature on solubility of a solute in a solvent.
Determine the effects of various salts on soap.

Worked examples.
Supervised practice.
Written assignment.
Experiments involving solubility of KClO3 at different temperatures.
Note temperatures at which crystallization occurs.
Oral questions and discussion.
Group experiments: form soap lather in distilled water, tap water, rainwater, dilute solution of sodium chloride and solutions containing Ca2+ and Zn2+.
Note volume of soap that forms lather readily.

Evaporating dish, watch glass, heating source, thermometer.

KClO3 thermometers, source of heat.
distilled water, tap water, rainwater, dilute solution of sodium chloride and solutions containing Ca2+ and Zn2+.

K.L.B. BK IV
Pages 21-22
K.L.B. BK IV
Pages 22-25

ACIDS, BASES AND SALTS.

Removal of hardness of water.

By the end of the lesson, the learner should be able to:
Identify ions for hardness of water.
Identify methods of removing hardness of water.
State merits & demerits of hard water.

Review results of above experiments.

Probing questions & brief discussion.

Assignment.

student book

K.L.B. BK IV
Pages 27-29