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.

pH values of acids. Electrical conductivities of aqueous acids.
Definition of a base in terms of hydroxide ions.
Neutralization reaction.

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.
1M HCl,
Calcium hydroxide,
universal indicator.

K.L.B. BK IV
Pages 4-6
K.L.B. BK IV
Pages 6-7

ACIDS, BASES AND SALTS.

Strength of bases.

By the end of the lesson, the learner should be able to:
Compare strengths of bases using pH values and electrical conductivity.


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

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.

2M NaOH,
2M ammonia solution, universal indicator solutions, dry cells,
carbon electrodes,
milliammeters,
wires, switches etc

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.

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.

By the end of the lesson, the learner should be able to:
Find out cations that form (in)soluble chlorides, sulphates and sulphites.

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.

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

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

ACIDS, BASES AND SALTS.

Equations for formation of insoluble chlorides, sulphites and sulphates.

By the end of the lesson, the learner should be able to:
Write down equations for formation of insoluble chlorides, sulphites and sulphates.

Q/A: review observations made in the above experiments.
Discuss the solubility of the cations.
Write relevant ionic equations.

student book

K.L.B. BK IV
Pages 17-18

ACIDS, BASES AND SALTS.

Complex ions.
Solubility of a salt at a given temperature.

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

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

Make observations and discuss the results.
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.

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

Suitable solutes.

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

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.

Experiments involving solubility of KClO3 at different temperatures.
Note temperatures at which crystallization occurs.
Oral questions and discussion.

KClO3 thermometers, source of heat.

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

ACIDS, BASES AND SALTS.

Effects of various salts on soap.

By the end of the lesson, the learner should be able to:
Determine the effects of various salts on soap.

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.

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

K.L.B. BK IV
Pages 25-27

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

Removal of hardness of water.
Endothermic and Exothermic Reactions.

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.

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.

student book






Ammonium nitrate,
Sodium hydroxide, thermometers.

K.L.B. BK IV
Pages 27-29
K.L.B. BK IV
Pages 32-33

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Energy level diagrams.

By the end of the lesson, the learner should be able to:
Represent endothermic reactions with exothermic reactions with energy level diagrams.

Probing questions on relative energies of reactants and products in endothermic and exothermic and endothermic reactions.

student book

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
K.L.B. BK IV
Pages 42-45

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Molar heat of solution of H2SO4.

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

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.

Conc. H2SO4, thermometers.

K.L.B. BK IV
Pages 42-45

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Enthalpy of combustion. Enthalpy of combustion.

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.

Group experiments / teacher demonstration.

Obtain and record results.


Work out calculations.

Ethanol, distilled water, thermometer, clear wick, tripod stand and wire gauze.

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

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Molar heat of displacement of ions.

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

Zinc, iron, magnesium, copper sulphate solution.

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

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Molar heat of displacement of ions.
Molar heat of solution of neutralization.

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

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.

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.

Zinc, iron, magnesium, copper sulphate solution.

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

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

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.

Exposition of new concepts.
Guided discovery of the relationship between heat solution hydration energy and lattice energy.
Worked examples.
Assignment.

student book

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

ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Heat values of fuels.
Environmental effects of fuels.

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

Probing questions and brief discussion.
Q/A & open discussion.

student book

K.L.B. BK IV
Pages 64-66
K.L.B. BK IV
Pages 67-68

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of temperature of reactants on rate of reaction.
Effect of change in surface area of reactants on the rate of a 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.
Marble chips, marble chips powder, syringes, conical flasks with stoppers, 1M HCl.

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

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of a suitable catalyst on the rate of a reaction

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

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.

Hydrogen peroxide, manganese (IV) oxide.

K.L.B. BK IV
Pages 85-88

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of light on rate of specific reactions.

By the end of the lesson, the learner should be able to:
Identify reactions that are affected by light.

Teacher demonstration: decomposition of silver bromide in the presence of light.
Mention other examples of reactions affected by light.

Silver bromide.

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

RATES OF REACTION & REVERSIBLE REACTIONS.

Reversible reactions.
State of equilibrium in chemical reactions.
Le Chatelier?s Principle.

By the end of the lesson, the learner should be able to:
Write down equations for reversible reactions.
State Le Chatelier?s Principle.

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.


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.

Crystals of hydrated copper (II) sulphate.
student book
Add 2M sodium hydroxide,

K.L.B. BK IV
Pages 91-93
K.L.B. BK IV
Pages 95-97

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of change of pressure and temperature on equilibrium shift.

By the end of the lesson, the learner should be able to:
Explain the effect of change of pressure & te,perature on equilibrium shift.

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.

student book

K.L.B. BK IV
Pages 97-101

RATES OF REACTION & REVERSIBLE REACTIONS.

The Haber Process.
The Contact 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

METALS

Ores of some metals.

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


Name the chief ores of some metals.

Exposition and brief discussion.

K.L.B. BK IV
Pages 168-9

METALS

Occurrence and extraction of sodium.
Occurrence and extraction of aluminium.
Occurrence and extraction of iron.

By the end of the lesson, the learner should be able to:
Describe occurrence and extraction of sodium.
Describe occurrence and extraction of iron.

Oral questions on electrolysis and equations at electrodes.
Brief discussion on occurrence and extraction.

Brief discussion.
Write relevant chemical equations.

Chart: Down?s cell.
student book
Chart: Blast furnace.

K.L.B. BK IV
Pages 170-171
K.L.B. BK IV
Pages 173-5

METALS

Occurrence and extraction of zinc.

By the end of the lesson, the learner should be able to:
Describe occurrence and extraction of zinc by electrolysis and reduction methods.

Brief discussion.
Write relevant chemical equations.

Flow chart: extraction of Zinc.

K.L.B. BK IV
Pages 175-9

METALS

Extraction of lead.

By the end of the lesson, the learner should be able to:
Explain how lead is extracted.

Q/A & brief discussion.
Write balanced chemical equations leading to extraction of lead.

Flow chart: extraction of lead.

K.L.B. BK IV
Pages 179-80

METALS

Occurrence and extraction of copper.

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

Q/A & brief discussion.
Write balanced chemical equations leading to extraction of copper.

Flow chart: extraction of copper.

K.L.B. BK IV
Pages 181-183

METALS

Physical properties of some metals.
Reaction of metals with oxygen.

By the end of the lesson, the learner should be able to:
State general properties of metals.
Explain the difference in physical properties of metals.
Explain effect of burning metals in air.

Compare physical properties of some metals as summarized in a chart.
Q/A & discussion based on physical properties.

Teacher demonstration / Group experiments.
Burning some metals in air.
Write relevant equations.
Brief discussion.

student book
Common lab. metals.

K.L.B. BK IV
Pages 183-4
K.L.B. BK IV
Pages 184-6

METALS

Reaction of metals with cold water and steam.

By the end of the lesson, the learner should be able to:
Describe reaction of metals with cold water and steam.

Arrange the metals in order of reactivity with cold water and steam.

Class experiments:
Investigate reaction of some metals with cold water and steam.
Analyse the results.

Metals: Al, Zn, Fe, Cu.

K.L.B. BK IV
Pages 186-9

METALS

Reaction of metals with chlorine.

By the end of the lesson, the learner should be able to:
Describe the reaction of metals with chlorine.

Teacher demonstration in a fume cupboard / in the open.
Investigate reaction of metals with chorine
Write corresponding equations.

Metals: Al, Zn, Fe, Cu.

K.L.B. BK IV
Pages 189-191

METALS

Reaction of metals with chlorine.

By the end of the lesson, the learner should be able to:
Describe the reaction of metals with chlorine.

Teacher demonstration in a fume cupboard / in the open.
Investigate reaction of metals with chorine
Write corresponding equations.

Metals: Al, Zn, Fe, Cu.

K.L.B. BK IV
Pages 189-191

METALS

Reaction of metals with acids.

By the end of the lesson, the learner should be able to:
Describe and explain reaction of metals with acids.

Group experiments: investigate reaction of metals with dilute acids.
Teacher demonstration: investigate reaction of metals with concentrated acids.
Discuss the observations made and write relevant chemical equations.

Metals: Al, Zn, Fe, Cu.

Acids; HCl, HNO3, H2SO4.

K.L.B. BK IV
Pages 191-4

METALS

Reaction of metals with acids.
Uses of metals.

By the end of the lesson, the learner should be able to:
Describe and explain reaction of metals with acids.
State uses of some metals and alloys.

Group experiments: investigate reaction of metals with dilute acids.
Teacher demonstration: investigate reaction of metals with concentrated acids.
Discuss the observations made and write relevant chemical equations.

Q/A & brief discussion;
Uses of Sodium, Aluminium, Zinc, Iron and Copper & some alloys.

Metals: Al, Zn, Fe, Cu.

Acids; HCl, HNO3, H2SO4.
student book

K.L.B. BK IV
Pages 191-4
K.L.B. BK IV
Pages 194-7

METALS

Environmental effects of extraction of metals.

By the end of the lesson, the learner should be able to:
Identify some environmental effects of extraction of metals.

Oral questions and open discussion.

Assignment / Topic review.

student book

K.L.B. BK IV
Pages 197-8