ENERGY CHANGES IN PHYSICAL & CHEMICAL PROCESSES.

Endothermic and Exothermic Reactions.

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






To differentiate between endothermic & exothermic reactions.

Investigate temperature changes in solution formation.

Obtain changes in temperature when ammonium nitrate and sodium hydroxide are dissolved in water, one at a time.

Ammonium nitrate,
Sodium hydroxide, thermometers.

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
Molar heat of solution.

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

Determine molar heat of solution of given substances.

Dissolve known masses of ammonia nitrate / sodium hydroxide in known volumes of water.
Determine temperature changes.
Calculate molar heat of solution. Supervised practice.

Ammonia nitrate / sodium hydroxide, thermometers.

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

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.

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.

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 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.

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.
Hess?s Law.

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.

State Hess?s law.

Solve problems related to Hess?s law.

Exposition & brief discussion.
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 54-56
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 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 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.
RATES OF REACTION & REVERSIBLE REACTIONS.

Heat values of fuels.
Environmental effects of fuels.
Effect of temperature of reactants on rate of reaction.

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.

Explain the effect of temperature on rate of reaction.

Probing questions and brief discussion.
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.

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

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

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.

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.

Marble chips, marble chips powder, syringes, conical flasks with stoppers, 1M HCl.

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

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.

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

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.

Crystals of hydrated copper (II) sulphate.
student book

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

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.

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.

The Contact Process.

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.

Probing questions and brief discussion.

Assignment.

student book

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

METALS

Ores of some metals.
Occurrence and extraction of sodium.

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


Name the chief ores of some metals.


Describe occurrence and extraction of sodium.

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

Chart: Down?s cell.

K.L.B. BK IV
Pages 168-9
K.L.B. BK IV
Pages 170-171

METALS

Occurrence and extraction of aluminium.

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

Brief discussion.
Write relevant chemical equations.

student book

K.L.B. BK IV
Pages 171-3

METALS

Occurrence and extraction of iron.

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

Brief discussion.
Write relevant chemical equations.

Chart: Blast furnace.

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.
Occurrence and extraction of copper.

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

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

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

Flow chart: extraction of lead.
Flow chart: extraction of copper.

K.L.B. BK IV
Pages 179-80
K.L.B. BK IV
Pages 181-183

METALS

Physical properties of some metals.

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.

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

student book

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

METALS

Reaction of metals with oxygen.

By the end of the lesson, the learner should be able to:
Explain effect of burning metals in air.

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

Common lab. metals.

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

METALS

Reaction of metals with oxygen.

By the end of the lesson, the learner should be able to:
Explain effect of burning metals in air.

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

Common lab. metals.

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 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.

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

Uses of metals.
Environmental effects of extraction of metals.

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

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

Oral questions and open discussion.

Assignment / Topic review.

student book

K.L.B. BK IV
Pages 194-7
K.L.B. BK IV
Pages 197-8