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.
Definition of a base in terms of hydroxide ions.

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.
Define a base in terms of hydroxide ions.

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.
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.

Universal
indicator,
2M HCl,
2M ethanoic acid,
dry cells,
carbon electrodes,
milli-ammeters,
wires, switches etc.
Red litmus paper, calcium hydroxide solid.

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

ACIDS, BASES AND SALTS.

Neutralization reaction.
Strength of bases.

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

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.

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

ACIDS, BASES AND SALTS.

Dissolving hydrogen chloride gas in water / methylbenzene.
Dissolving ammonia gas in water/ methylbenzene.

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

Teacher demonstration:
Dissolving HCl gas in different solvents.
Discuss the observations.
Write down related balanced chemical equations.
Carry out litmus tests on the resulting solution.
Make observations and deductions thereof.

Ammonia gas,
Methylbenzene, hydrogen chloride gas.
Methylbenzene.

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

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.

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

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.

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

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

ACIDS, BASES AND SALTS.

Solubility of chlorides sulphites and sulphates.
Equations for formation of insoluble chlorides, sulphites and sulphates.
Complex ions.

By the end of the lesson, the learner should be able to:
Find out cations that form (in)soluble chlorides, sulphates and sulphites.
Write down equations for formation of insoluble chlorides, sulphites and sulphates.
Explain formation of complex ions.

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

Make observations and discuss the results.

0.1M solution containing Pb2+, 2M NaCl solution, 2M sodium sulphate, source of heating.
student book
2M Sodium hydroxide (2M ammonia solution),
solution containing Mg2+, Zn2+, etc.

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

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.

Worked examples.
Supervised practice.
Written assignment.

Evaporating dish, watch glass, heating source, thermometer.

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

ACIDS, BASES AND SALTS.

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:
Investigate the effect of temperature on solubility of a solute in a solvent.
Determine the effects of various salts on soap.

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.

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 22-25

ACIDS, BASES AND SALTS.
ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Removal of hardness of water.
Endothermic and Exothermic Reactions.
Energy level diagrams.

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.
To differentiate between endothermic & exothermic reactions.
Represent endothermic reactions with exothermic reactions with energy level diagrams.

Review results of above experiments.
Probing questions & brief discussion.
Assignment.
Investigate temperature changes in solution formation.
Obtain changes in temperature when ammonium nitrate and sodium hydroxide are dissolved in water, one at a time.
Probing questions on relative energies of reactants and products in endothermic and exothermic and endothermic reactions.

student book
Ammonium nitrate,
Sodium hydroxide, thermometers.

K.L.B. BK IV
Pages 27-29
K.L.B. BK IV
Pages 33-35

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Enthalpy Notation. Change of state.

By the end of the lesson, the learner should be able to:
Define the term enthalpy.
Distinguish positive enthalpy change from negative enthalpy change.

Determine the M.P/ B.P of a pure substance.

Q/A and brief discussion.
Class experiments: determine B.P of pure water/ M.P of naphthalene / ice.
Use experimental results to plot temperature-time graphs.
Explain the shape of the graphs.
Q/A: review kinetic theory of matter.
Apply the theory to explain the shape of the graph, and nature of bonding in substances.

Ice, naphthalene, thermometers, graph papers.

K.L.B. BK IV
Pages 35-39

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

CAT

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

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Molar heat of solution.
Molar heat of solution of H2SO4.

By the end of the lesson, the learner should be able to:
Determine molar heat of solution of given substances.
Determine molar heat of solution of H2SO4.

Dissolve known masses of ammonia nitrate / sodium hydroxide in known volumes of water.
Determine temperature changes.
Calculate molar heat of solution. Supervised practice.
Dissolve some known volume of conc. H2SO4 in a given volume of water.
Note the change in temperature.
Work out the molar heat of solution of H2SO4.

Ammonia nitrate / sodium hydroxide, thermometers.
Conc. H2SO4, thermometers.

K.L.B. BK IV
Pages 40-41

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Enthalpy of combustion. Enthalpy of combustion.
Molar heat of displacement of ions.

By the end of the lesson, the learner should be able to:
Define the term enthalpy of combustion.
Determine the enthalpy of combustion of ethanol.
Explain why actual heats of combustion are usually lower than the theoretical values.

Define the term molar heat of solution of displacement of ions.
Determine the molar heat of solution of displacement of ions.

Group experiments / teacher demonstration.

Obtain and record results.


Work out calculations.
Group experiments/ teacher demonstration.
Note steady temperature of solutions formed when zinc/ iron / magnesium reacts with copper sulphate solution.
Work out the molar heat of displacement of a substance from a solution of its ions.

Ethanol, distilled water, thermometer, clear wick, tripod stand and wire gauze.
Zinc, iron, magnesium, copper sulphate solution.

K.L.B. BK IV
Pages 45-48
K.L.B. BK IV
Pages 48-50

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Molar heat of solution of neutralization.

By the end of the lesson, the learner should be able to:
Define the term neutralization.
Determine the molar heat of neutralization of HCl with NaOH.

Class experiments:
Neutralize 2M HCl of known volume with a determined volume of 1M / 2M sodium hydroxide.
Note highest temperature of the solution.
Work out the molar heat of neutralization.
Solve other related problems.
Assignment.

2M HCl of known volume, 1M / 2M sodium hydroxide.

K.L.B. BK IV
Pages 50-53

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Standard enthalpy changes.

By the end of the lesson, the learner should be able to:
Define the term standard enthalpy change.
Denote standard enthalpy change with the correct notation.

Exposition & brief discussion.

student book

K.L.B. BK IV
Pages 54-56

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Hess?s Law.

By the end of the lesson, the learner should be able to:
State Hess?s law.

Solve problems related to Hess?s law.

Detailed discussion & guided discovery of the law.
Illustrations of energy cycles and energy levels leading to Hess?s law.
Worked examples.
Supervised practice
Written assignment.

student book

K.L.B. BK IV
Pages 56-57

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Heat of solution hydration energy and lattice energy.
Heat values of fuels.
Environmental effects of fuels.

By the end of the lesson, the learner should be able to:
Define the terms lattice energy and hydration energy.
Explain the relationship between heat of solution, hydration energy.
Solve related problems.
Define the term fuel.
Describe energy changes when a fuel undergoes combustion.
Outline factors considered when choosing a suitable fuel.
Outline some environmental effects of fuels.
Identify measures taken to reduce environmental
pollution.

Exposition of new concepts.
Guided discovery of the relationship between heat solution hydration energy and lattice energy.
Worked examples.
Assignment.
Probing questions and brief discussion.
Q/A & open discussion.

student book

K.L.B. BK IV
Pages 60-64
K.L.B. BK IV
Pages 67-68

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of concentration on rate of a reaction
Effect of time of reaction on the rate of reaction.

By the end of the lesson, the learner should be able to:
Explain the effects of change of concentration of reactants on a reaction.
Explain how the rate or reaction changes as the reaction proceed

Group experiments to investigate effect of concentration on rate of reaction using dil. HCl and magnesium ribbons.
Determine the time taken for reactions to be complete.
Calculation of concentration of HCl in moles per litre.
Discuss the observations and sketch illustrative graphs.
Group experiments: investigate volume of gas evolved when magnesium reacts with dilute HCl.
Collect evolved gas and sketch and illustrative graphs.
Discuss the results.

Portions of 2M HCl diluted with different volumes of water,
Stopwatches.
Magnesium ribbons, stopwatches, conical flask.
100cm3 0.5M HCl, syringes, stoppers, tubes and connectors.

K.L.B. BK IV
Pages 73-74

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of temperature of reactants on rate of reaction.

By the end of the lesson, the learner should be able to:
Explain the effect of temperature on rate of reaction.

Group experiments: investigate the effects of temperature on the rate of reaction of sodium thiosulphate with dilute HCl.
Sketch and interpret relevant graphs.
Discuss the collision theory and effects of activation energy.

Sodium thiosulphate heated at different temperatures, dilute HCl, stopwatches.
Graph papers.

K.L.B. BK IV
Pages 80-83

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of change in surface area of reactants on the rate of a reaction.
Effect of a suitable catalyst on the rate of a reaction

By the end of the lesson, the learner should be able to:
Explain the effect of change in surface area on the rate of a reaction.
Explain effects of a suitable catalyst on the rate of a reaction.

Group experiment/ teacher demonstration.
Compare reactions of marble chips with dilute HCl and that of marble chips powder with equally diluted HCl.
Collect evolved gas in each case.
Teacher asks probing questions related to the observations made.
Teacher demonstration: preparation and collection of oxygen gas without using a catalyst, then using manganese (IV) oxide as a catalyst.
Explain the results in terms of activation energy.

Marble chips, marble chips powder, syringes, conical flasks with stoppers, 1M HCl.
Hydrogen peroxide, manganese (IV) oxide.

K.L.B. BK IV
Pages 83-85

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of light on rate of specific reactions.
Reversible reactions.
State of equilibrium in chemical reactions.

By the end of the lesson, the learner should be able to:
Identify reactions that are affected by light.
Write down equations for reversible reactions.
Define the term equilibrium as used in reversible reactions.
Write down equations of reversible reactions in a state of equilibrium.

Teacher demonstration: decomposition of silver bromide in the presence of light.
Mention other examples of reactions affected by light.
Q/A: review temporary and permanent changes.
Teacher demonstration: heating crystals of hydrated copper (II) sulphate, then ?hydrating? them.
Write the corresponding chemical equations.
Give further examples of reversible reactions.
Brief discussion, giving examples of chemical equations for reversible reactions.

Silver bromide.
Crystals of hydrated copper (II) sulphate.
student book

K.L.B. BK IV
Pages 89-91
K.L.B. BK IV
Pages 94-95

RATES OF REACTION & REVERSIBLE REACTIONS.

Le Chatelier?s Principle.
Effect of change of pressure and temperature on equilibrium shift.

By the end of the lesson, the learner should be able to:
State Le Chatelier?s Principle.
Explain the effect of change of pressure & te,perature on equilibrium shift.

Investigate the effect of change of concentration of reactants on equilibrium.
Add 2M sodium hydroxide in steps to bromine water.
Make and record observations.
Discuss the results leading to
Le Chatelier?s Principle.
Q/A: review kinetic theory of matter.
Q/A & discussion on effect of change of pressure / temperature on shifting of equilibrium; giving specific examples of chemical equations.
Written assignment.

Add 2M sodium hydroxide,
student book

K.L.B. BK IV
Pages 95-97

RATES OF REACTION & REVERSIBLE REACTIONS.

The Haber Process.

By the end of the lesson, the learner should be able to:
Explain the concept optimum conditions of a chemical equilibrium.
Explain factors that change the position of equilibrium of the Harber process.

Q/A and detailed discussion on change of pressure, temperature, concentration of ammonia and effect of presence of a suitable catalyst on the Haber process.

student book

K.L.B. BK IV
Pages 102-103

RATES OF REACTION & REVERSIBLE REACTIONS.
ELECTRO-CHEMISTRY.

The Contact Process.
Redox reactions.

By the end of the lesson, the learner should be able to:
Explain how change of temperature and pressure affect rate of manufacture of sulphur (VI) acid.
Describe redox reactions in terms of gain / loss of electrons.
Identify oxidizing / reducing agents involved in redox reactions.

Probing questions and brief discussion.
Assignment.
Q/A: review cations, anions and charges.
Write down ionic half equations and identify reducing / oxidizing agents.

student book

K.L.B. BK IV
Pages 103-104

ELECTRO-CHEMISTRY.

Oxidizing Numbers.
Displacement reactions.
The oxidizing power of an element.

By the end of the lesson, the learner should be able to:
Outline rules of assigning oxidation numbers.
Determine the oxidation numbers of an element in a given compound.
Explain the use of oxidation numbers in naming compounds.
Explain change of oxidation numbers during redox / displacement reactions. Arrange elements in order of their reducing power.
Arrange elements in order of their oxidizing power.

Exposition and giving specific examples.
Work out oxidizing number of elements in given compounds.
Copy and complete a table of compounds containing elements that more than one oxidation number.

Class standard experiments: reacting metals with solutions containing metal ions.
Taking note of reactions and those that do not take place; and tabulating the results.
Teacher demonstration / group expts:
Adding halogens to solutions containing halide ions.
Tabulate the results.
Discuss the results and arrive at the oxidizing power series of halogens.

student book
Metals: Ca, Na, Zn, Fe, Pb, and Cu.
Solutions containing Ca2+, Mg2+, Zn2+, Fe2+.
Halogens:
Cl2 (g),
Br2 (l),
I2 (s).
Halides:
KCl, KBr, KI.

K.L.B. BK IV
Pages 109-116
K.L.B. BK IV
Pages 116-120

ELECTRO-CHEMISTRY.

Cell diagrams.

By the end of the lesson, the learner should be able to:
Define the terms electrode, potential and e.m.f. of an electrochemical cell.
Describe components of a cell diagram.
Draw cell diagrams using correct notations.

Teacher demonstration: Zinc/ copper cell.
Q/A & discussion: changes in oxidation numbers.
Exposition: cell diagram and deducing the direction of electron flow.

Zinc/ copper cell.

K.L.B. BK IV
Pages 123-128

ELECTRO-CHEMISTRY.

Standard Electrode Potentials.
Standard electrode potential series.

By the end of the lesson, the learner should be able to:
Identify standard conditions for measuring electrode potentials.
Define the term standard electrode potential of a cell.
Write half reactions of electrochemical cells.
Recall the order of standard electrode potentials.
Compare oxidizing and reducing powers of substances.

Descriptive and expository approaches: teacher exposes new concepts.
Q/A: review reactivity series, oxidizing agent, reducing agent.
Exposition: the order of standard electrode potentials.
Discussion: oxidizing and reducing powers of substances.

student book

K.L.B. BK IV
Pages 129-131

ELECTRO-CHEMISTRY.

Emf of a cell.

By the end of the lesson, the learner should be able to:
Calculate emf of a cell using standard electrodes potentials.

Q/A: review half-cells.
Worked examples; supervised practice.
Assignment.

student book

K.L.B. BK IV
Pages 133-136

ELECTRO-CHEMISTRY.

Possibility of a reaction to take place.
Primary and secondary chemical cells.
Electrolysis of dilute NaCl.

By the end of the lesson, the learner should be able to:
Predict whether a reaction will take place or not using standard electrode potentials.
Describe the functioning of primary and secondary chemical cells.
Define the term electrolysis.
Explain the concept of preferential discharge of ions.

Worked examples.
Oral exercise.
Assignment.
Exposition of new concepts and brief discussion
Teacher demonstration: electrolysis of dilute sodium chloride with carbon electrodes.
Test for gases collected.
Write down equations of reactions at each electrode.
Discussion: preferential discharge of ions at electrodes.

student book
Dilute sodium chloride voltameter.

K.L.B. BK IV
Pages 136-137
K.L.B. BK IV
Pages 141-144

ELECTRO-CHEMISTRY.

Electrolysis of brine.
Electrolysis of dilute sulphuric (VI) acid.

By the end of the lesson, the learner should be able to:
Identify products of electrolysis of brine.
Identify products of electrolysis of dilute sulphuric (VI) acid.

Teacher demonstration/ group experiments.
Test for the products of electrolysis.
Write relevant equations.

Brine voltameter.
Sulphuric acid voltameter.

K.L.B. BK IV
Pages 144-146

ELECTRO-CHEMISTRY.

Factors affecting electrolysis.

By the end of the lesson, the learner should be able to:
Explain factors that affect electrolytic products discharged at electrodes.

Q/A: review the electrochemical series of elements.
Teacher writes down order of ease of discharge of ions at electrodes.
Discussion: other factors; giving suitable examples.

student book

K.L.B. BK IV
Pages 153-5

ELECTRO-CHEMISTRY.

Application of electrolysis.
Faraday?s law of electrolysis.

By the end of the lesson, the learner should be able to:
Describe some applications of electrolysis.
State Faraday?s law of electrolysis.
Solve problems related to Faraday?s law of electrolysis.

Probing questions and brief discussion on applications of electrolysis.
Practical assignment on electrolysis: electroplating an iron nail with a suitable metal.
Discuss above results, leading to Faraday?s law of electrolysis.
Worked examples.
Assignment.

Suitable voltameter.
Weighing balance, stop watch, copper sulphate voltameter.

K.L.B. BK IV
Pages 155-7

RADIOACTIVITY

Definition of radioactivity.
Alpha particles.
Equations involving alpha particles.
Beta particles. Gamma rays.
Radioactive Half-Life.

By the end of the lesson, the learner should be able to:
Define radioactivity, a nuclide and radioactive decay.
Differentiate between natural and artificial radioactivity.
State properties of alpha particles.
Describe methods of detecting alpha particles.
Write down and balance equations involving alpha particles.
State properties of beta particles.
Define isotopes and isobars.
Write down balanced equations involving both alpha and beta particles.
State properties of gamma rays.
Define the term radioactive half-life. Solve problems relating to half ?life

Q/A: Review the atomic structure.
Exposition: symbolic representation of an atom / nucleus.
Exposition: meaning of radioactivity and radioactive decay.
Discussion: artificial and natural radioactivity.

Q/A: position of helium in the periodic table.
Expository approach:
Q/A: Review atomic and mass numbers.
Examples of balanced equations.
Supervised practice.
Q/A: Review isotopes.
Expository approach: teacher briefly exposes new concepts.
Examples of equations.
Supervised practice.
Assignment.
Teacher demonstration: Dice experiment.
Exposition of the term half-life.
Worked examples.
Written exercise

student book
student book
Dice.

K.L.B. BK IV
Pages 249-251
K.L.B. BK IV
Page 257

RADIOACTIVITY

Radioactive decay curve.
Nuclear fusion and nuclear fission. Applications of radioactivity.

By the end of the lesson, the learner should be able to:
Plot a radioactive decay curve to deduce the
half ?life from the curve.
Differentiate between nuclear fusion and nuclear fission.
Describe applications of radioactivity.

Drawing a radioactive decay curve inferring the half-life of the sample from the graph.
Exposition of new concepts accompanied by nuclear equations.
Brief discussion: Carbon dating, detecting leakage, medication, agriculture, industry; effect of static charges, etc.

Graph papers.
student book

K.L.B. BK IV
Pages 254-5