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.

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.

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.

Red litmus paper, calcium hydroxide solid.
1M HCl,
Calcium hydroxide,
universal indicator.

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.
Amphoteric oxides.

By the end of the lesson, the learner should be able to:
Investigate effect of a polar / non-polar solvent on ammonia gas.
Define an amphoteric oxide.
Identify some amphoteric oxides.

Carry out litmus tests on the resulting solution.
Make observations and deductions thereof.
Write down related balanced chemical equations.
Class experiment:
Carry out acid / base reactions with metal oxides.
Q/A: make deductions from the results.
Writing and balancing relevant equations.

Ammonia gas,
Methylbenzene.
2M Nitric acid
2M NaOH,
HNO3.
Amphoteric oxides.

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

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.

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.

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.

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

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.

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.

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.
Removal of hardness of water.

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

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.

Review results of above experiments.

Probing questions & brief discussion.

Assignment.

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

K.L.B. BK IV
Pages 25-27
K.L.B. BK IV
Pages 27-29

RATES OF REACTION & REVERSIBLE REACTIONS.

Effect of concentration on 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.

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.

Portions of 2M HCl diluted with different volumes of water,
Stopwatches.

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

RATES OF REACTION & REVERSIBLE REACTIONS.
ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Effect of time of reaction on the rate of reaction.
Alkanols (Alcohols).

By the end of the lesson, the learner should be able to:
Explain how the rate or reaction changes as the reaction proceed
Identify the functional group of alkanols.
Explain formation of alkanol molecules.

Group experiments: investigate volume of gas evolved when magnesium reacts with dilute HCl.
Collect evolved gas and sketch and illustrative graphs.
Discuss the results.
Q/A: review alkanes, alkenes and alkynes.
Teacher exposes new concepts and links them with already known concepts.

Magnesium ribbons, stopwatches, conical flask.
100cm3 0.5M HCl, syringes, stoppers, tubes and connectors.
student book

K.L.B. BK IV
Pages 75-79

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Nomenclature of alkanols.

By the end of the lesson, the learner should be able to:
Name and draw the structure of simple alkanols.

Guided discovery of naming system for alkanols.
Draw and name structures of alkanols.

student book

K.L.B. BK IV
Pages 206-8

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Isomerism in alkanols.
Preparation of ethanol in the lab.

By the end of the lesson, the learner should be able to:
Describe positional and chain isomerism in alkanols.
Explain formation of primary and secondary alkanols.
Describe preparation of ethanol in the laboratory.

Q/A: review the terms positional and chain isomerism.
Brief discussion on isomerism.
Oral exercise: naming given organic compounds.
Written exercise: writing structural formulae for isomers of organic compounds of a given molecular formula.

Group experiments / teacher demonstration.

Discuss the fermentation process.

student book
Calcium hydroxide solution, sugar solution, yeast.

K.L.B. BK IV
Pages 208-10
K.L.B. BK IV
Pages 210-11

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Physical properties of alkanols.

By the end of the lesson, the learner should be able to:
Explain the physical properties of alkanols.

Comparative evaluation of physical properties of alkanols.
Q/A & discussion on variation in physical properties of alkanols.

student book

K.L.B. BK IV
Page 212

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Chemical properties of alkanols.
Esters and esterification.

By the end of the lesson, the learner should be able to:
Describe some chemical reactions of alkanols.
Explain formation of esters.
Describe the esterification process.

Group experiments/ teacher demonstration to investigate combustion of ethanol and its reaction with metals.
Write corresponding chemical equations.
Teacher exposes and explains new concepts.
Assignment.

student book

K.L.B. BK IV
Pages 213-5

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Oxidation of ethanol. Uses of alkanols.

By the end of the lesson, the learner should be able to:
Explain oxidation of ethanol by an oxidizing agent.
State uses of alkanols.
Explain the effects of alcohol on human health

Q/A: review redox reactions, oxidizing and reducing agents.
Brief discussion: oxidation of ethanol using potassium (VII) manganate or potassium (VI) dichromate.
Write corresponding chemical equations.
Open discussion.

student book

K.L.B. BK IV
Pages 216-8

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Alkanoic (Carboxylic Acids).

By the end of the lesson, the learner should be able to:
Identify the functional group of alkanoic (carboxylic) acids.
Explain formation of alkanoic acid molecule.

Q/A: review functional group of alkanols.

Brief discussion.

student book

K.L.B. BK IV
Page 219

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Nomenclature of alkanoic acids.

By the end of the lesson, the learner should be able to:
Name and draw the structure of simple alkanoic acids.

Guided discovery of the naming system for alkanoic acids.

Chart: homologous series of alkanoic acids.

K.L.B. BK IV
Pages 219-221

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Lab preparation of ethanoic acid.

By the end of the lesson, the learner should be able to:
Describe laboratory preparation of ethanoic acid.

Teacher demonstration: prepare ethanoic acid in the lab.

Brief discussion on preparation of ethanoic acid.

Concentrated H2SO4, potassium manganate
(VII) Crystals, water bath.

K.L.B. BK IV
Pages 221-223

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Physical properties of alkanoic acids.

By the end of the lesson, the learner should be able to:
Explain some physical properties of alkanoic acids.

Compare physical properties of some alkanoic acids.
Discuss the difference in physical properties among alkanoic acids.

student book

K.L.B. BK IV
Pages 223-4

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Chemical properties of alkanoic acids.
Chemical properties & Uses of alkanoic acids.
Soap preparation in the lab.

By the end of the lesson, the learner should be able to:
Explain some chemical properties of alkanoic acids.
Write equations for chemical reactions involving acids.
State uses of alkanoic acids.
Describe soap preparation in the lab.

Group experiment: investigate some chemical properties of ethanoic acid.
Carry out tests and record observations in a table.
Review and discuss the observations above.
Write corresponding chemical equations.
Teacher elucidates uses of alkanoic acids.
Group experiments,
Answer questions based on the experiments already carried out.

Ethanoic acid, universal indicator, sodium carbonate, magnesium strip, ethanol, conc. H2SO4 and sodium hydroxide.
student book

K.L.B. BK IV
Pages 224-5
K.L.B. BK IV
Pages 227-230

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Cleaning action of soap.

By the end of the lesson, the learner should be able to:
Describe the nature of a soap molecule.
Explain the mode of action in cleaning.

Expository and descriptive approaches.
Answer oral questions.

student book

K.L.B. BK IV
Pages 230-232

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Effects of hard / soft water on soap.
Soapless detergents.

By the end of the lesson, the learner should be able to:
Explain the effects of hard/ soft water on soap.
Prepare soapless detergents in the lab.
State merits of soapless detergents over soaps.

Group experiments: form soap lather in different solutions.
Deduce the effects of hard/ soft water on soap.
Teacher demonsration.
Brief discussion.

Distilled water, tap water, rainwater, sodium chloride solution.
Calcium nitrate, Zinc Sulphate, etc.
student book

K.L.B. BK IV
Pages 232-235

ORGANIC CHEMISTRY II (ALKANES & ALKANOIC ACIDS)

Polymers and polymerization.

By the end of the lesson, the learner should be able to:
Explain the concepts additional and condensation polymerization as methods of making synthetic polymers.
Identify some products of polymerization.
State merits and demerits of synthetic polymers over natural materials.

Teacher exposes and explains new concepts.

Detailed discussion.

Assignment.

student book

K.L.B. BK IV
Pages 238-242