RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of concentration on rate of a reaction
Effect of time of reaction on the rate of reaction.
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 effects of change of concentration of reactants on a reaction.
Explain how the rate or reaction changes as the reaction proceed
Explain the effect of temperature on rate of reaction.
Explain the effect of change in surface area on the rate of a reaction.

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.
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.
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.

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.
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 73-74
K.L.B. BK IV
Pages 80-83

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of a suitable catalyst on the rate of a reaction
Effect of light on rate of specific reactions.

By the end of the lesson, the learner should be able to:
Explain effects of a suitable catalyst on the rate of a reaction.
Identify reactions that are affected by light.

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

Hydrogen peroxide, manganese (IV) oxide.
Silver bromide.

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

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

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.
ELECTRO-CHEMISTRY.

The Haber Process.
The Contact Process.
Redox reactions.
Oxidizing Numbers.

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.
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.
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.

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

student book

K.L.B. BK IV
Pages 102-103
K.L.B. BK IV
Pages 108-9

ELECTRO-CHEMISTRY.

Displacement reactions.

By the end of the lesson, the learner should be able to:
Explain change of oxidation numbers during redox / displacement reactions. Arrange elements in order of their reducing power.

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.

Metals: Ca, Na, Zn, Fe, Pb, and Cu.
Solutions containing Ca2+, Mg2+, Zn2+, Fe2+.

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

ELECTRO-CHEMISTRY.

The oxidizing power of an element.
Cell diagrams.

By the end of the lesson, the learner should be able to:
Arrange elements in order of their oxidizing power.
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 / group expts:
Adding halogens to solutions containing halide ions.
Tabulate the results.
Discuss the results and arrive at the oxidizing power series of halogens.
Teacher demonstration: Zinc/ copper cell.
Q/A & discussion: changes in oxidation numbers.
Exposition: cell diagram and deducing the direction of electron flow.

Halogens:
Cl2 (g),
Br2 (l),
I2 (s).
Halides:
KCl, KBr, KI.
Zinc/ copper cell.

K.L.B. BK IV
Pages 120-122

ELECTRO-CHEMISTRY.

Standard Electrode Potentials.

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.

Descriptive and expository approaches: teacher exposes new concepts.

student book

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

ELECTRO-CHEMISTRY.

Standard electrode potential series.
Emf of a cell.
Possibility of a reaction to take place.
Primary and secondary chemical cells.

By the end of the lesson, the learner should be able to:
Recall the order of standard electrode potentials.
Compare oxidizing and reducing powers of substances.
Calculate emf of a cell using standard electrodes potentials.
Predict whether a reaction will take place or not using standard electrode potentials.
Describe the functioning of primary and secondary chemical cells.

Q/A: review reactivity series, oxidizing agent, reducing agent.
Exposition: the order of standard electrode potentials.
Discussion: oxidizing and reducing powers of substances.
Q/A: review half-cells.
Worked examples; supervised practice.
Assignment.
Worked examples.
Oral exercise.
Assignment.
Exposition of new concepts and brief discussion

student book

K.L.B. BK IV
Pages 131-133
K.L.B. BK IV
Pages 136-137

ELECTRO-CHEMISTRY.

Electrolysis of dilute NaCl.

By the end of the lesson, the learner should be able to:
Define the term electrolysis.
Explain the concept of preferential discharge of ions.

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.

Dilute sodium chloride voltameter.

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.
Application of electrolysis.

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

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.
Probing questions and brief discussion on applications of electrolysis.
Practical assignment on electrolysis: electroplating an iron nail with a suitable metal.

student book
Suitable voltameter.

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

ELECTRO-CHEMISTRY.
METALS

Faraday?s law of electrolysis.
Ores of some metals.
Occurrence and extraction of sodium.
Occurrence and extraction of aluminium.

By the end of the lesson, the learner should be able to:
State Faraday?s law of electrolysis.
Solve problems related to Faraday?s law of electrolysis.
Name the chief ores of some metals.
Describe occurrence and extraction of sodium.
Describe occurrence and extraction of aluminium.

Discuss above results, leading to Faraday?s law of electrolysis.
Worked examples.
Assignment.
Exposition and brief discussion.
Oral questions on electrolysis and equations at electrodes.
Brief discussion on occurrence and extraction.
Brief discussion.
Write relevant chemical equations.

Weighing balance, stop watch, copper sulphate voltameter.
Chart: Down?s cell.
student book

K.L.B. BK IV
Pages 161-4
K.L.B. BK IV
Pages 170-171

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.
Extraction of lead.

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

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

Flow chart: extraction of Zinc.
Flow chart: extraction of lead.

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

METALS

Occurrence and extraction of copper.
Physical properties of some metals.

By the end of the lesson, the learner should be able to:
Describe extraction of copper.
State general properties of metals.
Explain the difference in physical properties of metals.

Q/A & brief discussion.
Write balanced chemical equations leading to extraction of copper.
Compare physical properties of some metals as summarized in a chart.
Q/A & discussion based on physical properties.

Flow chart: extraction of copper.
student book

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

METALS

Reaction of metals with oxygen.
Reaction of metals with cold water and steam.

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

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

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

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

Common lab. metals.
Metals: Al, Zn, Fe, Cu.

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

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