THE MOLE

Relative Mass - Introduction and Experimental Investigation
Avogadro's Constant and the Mole Concept
Interconversion of Mass and Moles for Elements
Molecules and Moles - Diatomic Elements

By the end of the lesson, the learner should be able to:
Define relative mass using practical examples
Compare masses of different objects using a reference standard
Explain the concept of relative atomic mass
Identify carbon-12 as the reference standard
Apply the formula: moles = mass/molar mass
Calculate mass from given moles of elements
Convert between moles and number of atoms
Solve numerical problems involving moles and mass

Experiment: Weighing different sized nails using beam balance. Use smallest nail as reference standard. Q/A: Discuss everyday examples of relative measurements. Teacher exposition: Introduction of carbon-12 scale and IUPAC recommendations. Calculate relative masses from experimental data.
Worked examples: Mass-mole conversions using triangle method. Supervised practice: Calculate moles in given masses of common elements. Problem solving: Convert moles to atoms using Avogadro's number. Assignment: Practice problems on interconversion.

Different sized nails ( 5-15cm), Beam balance, Fruits of different masses, Reference charts
Beam balance, Various sized nails, Scientific calculators, Avogadro's constant charts
Scientific calculators, Periodic table, Worked example charts, Formula triangles
Molecular models, Charts showing diatomic elements, Scientific calculators

KLB Secondary Chemistry Form 3, Pages 25-27
KLB Secondary Chemistry Form 3, Pages 30-32

THE MOLE

Empirical Formula - Experimental Determination

By the end of the lesson, the learner should be able to:
Define empirical formula
Determine empirical formula from experimental data
Calculate mole ratios from mass data
Express results as simplest whole number ratios

Experiment: Burning magnesium in air to form magnesium oxide. Measure masses before and after reaction. Calculate moles of Mg and O from mass data. Determine mole ratio and empirical formula. Safety precautions during heating.

Crucible and lid, Magnesium ribbon, Bunsen burner, Beam balance, Tongs, Safety equipment

KLB Secondary Chemistry Form 3, Pages 32-35

THE MOLE

Empirical Formula - Reduction Method
Empirical Formula - Percentage Composition Method

By the end of the lesson, the learner should be able to:
Determine empirical formula using reduction reactions
Calculate empirical formula from reduction data
Apply reduction method to copper oxides
Analyze experimental errors and sources

Experiment: Reduction of copper(II) oxide using laboratory gas. Measure masses before and after reduction. Calculate moles of copper and oxygen. Determine empirical formula from mole ratios. Discuss experimental precautions.

Combustion tube, Porcelain boat, Copper(II) oxide, Laboratory gas, Beam balance, Bunsen burner
Scientific calculators, Percentage composition charts, Worked example displays

KLB Secondary Chemistry Form 3, Pages 35-37

THE MOLE

Molecular Formula - Determination from Empirical Formula

By the end of the lesson, the learner should be able to:
Define molecular formula
Relate molecular formula to empirical formula
Calculate molecular formula using molecular mass
Apply the relationship (empirical formula)ₙ = molecular formula

Teacher exposition: Difference between empirical and molecular formulas. Worked examples: Calculate molecular formula from empirical formula and molecular mass. Formula: n = molecular mass/empirical formula mass. Practice problems with various organic compounds.

Scientific calculators, Molecular mass charts, Worked example displays

KLB Secondary Chemistry Form 3, Pages 38-40

THE MOLE

Molecular Formula - Combustion Analysis
Concentration and Molarity of Solutions
Preparation of Molar Solutions
Dilution of Solutions

By the end of the lesson, the learner should be able to:
Determine molecular formula from combustion data
Calculate moles of products in combustion
Relate product moles to reactant composition
Apply combustion analysis to hydrocarbons
Describe procedure for preparing molar solutions
Use volumetric flasks correctly
Calculate masses needed for specific molarities
Prepare standard solutions accurately

Worked examples: Hydrocarbon combustion producing CO₂ and H₂O. Calculate moles of C and H from product masses. Determine empirical formula, then molecular formula. Practice: Various combustion analysis problems.
Experiment: Prepare 1M, 0.5M, and 0.25M NaOH solutions in different volumes. Use volumetric flasks of 1000cm³, 500cm³, and 250cm³. Calculate required masses. Demonstrate proper dissolution and dilution techniques.

Scientific calculators, Combustion analysis charts, Molecular models of hydrocarbons
Scientific calculators, Molarity charts, Various salt samples for demonstration
Volumetric flasks (250, 500, 1000cm³), Sodium hydroxide pellets, Beam balance, Wash bottles, Beakers
Volumetric flasks, Hydrochloric acid (2M), Measuring cylinders, Pipettes, Safety equipment

KLB Secondary Chemistry Form 3, Pages 40-41
KLB Secondary Chemistry Form 3, Pages 43-46

THE MOLE

Stoichiometry - Experimental Determination of Equations

By the end of the lesson, the learner should be able to:
Determine chemical equations from experimental data
Calculate mole ratios from mass measurements
Write balanced chemical equations
Apply stoichiometry to displacement reactions

Experiment: Iron displacement of copper from CuSO₄ solution. Measure masses of iron used and copper displaced. Calculate mole ratios. Derive balanced chemical equation. Discuss spectator ions.

Iron filings, Copper(II) sulphate solution, Beam balance, Beakers, Filter equipment

KLB Secondary Chemistry Form 3, Pages 50-53

THE MOLE

Stoichiometry - Precipitation Reactions
Stoichiometry - Gas Evolution Reactions

By the end of the lesson, the learner should be able to:
Investigate stoichiometry of precipitation reactions
Determine mole ratios from volume measurements
Write ionic equations for precipitation
Analyze limiting and excess reagents

Experiment: Pb(NO₃)₂ + KI precipitation reaction. Use different volumes to determine stoichiometry. Measure precipitate heights. Plot graphs to find reaction ratios. Identify limiting reagents.

Test tubes, Lead(II) nitrate solution, Potassium iodide solution, Burettes, Ethanol, Rulers
Conical flask, Thistle funnel, Plastic bags, Rubber bands, Sodium carbonate, HCl solution

KLB Secondary Chemistry Form 3, Pages 53-56

THE MOLE

Volumetric Analysis - Introduction and Apparatus

By the end of the lesson, the learner should be able to:
Define volumetric analysis and titration
Identify and use titration apparatus correctly
Explain functions of pipettes and burettes
Demonstrate proper reading techniques

Practical session: Familiarization with pipettes and burettes. Practice filling and reading burettes accurately. Learn proper meniscus reading. Use pipette fillers safely. Rinse apparatus with appropriate solutions.

Pipettes (10, 20, 25cm³), Burettes (50cm³), Pipette fillers, Conical flasks, Various solutions

KLB Secondary Chemistry Form 3, Pages 58-59

THE MOLE

Titration - Acid-Base Neutralization
Titration - Diprotic Acids
Standardization of Solutions
Back Titration Method

By the end of the lesson, the learner should be able to:
Perform acid-base titrations accurately
Use indicators to determine end points
Record titration data properly
Calculate average titres from multiple readings
Define standardization process
Standardize HCl using Na₂CO₃ as primary standard
Calculate accurate concentrations from titration data
Understand importance of primary standards

Experiment: Titrate 25cm³ of 0.1M NaOH with 0.1M HCl using phenolphthalein. Repeat three times for consistency. Record data in tabular form. Calculate average titre. Discuss accuracy and precision.
Experiment: Prepare approximately 0.1M HCl and standardize using accurately weighed Na₂CO₃. Use methyl orange indicator. Calculate exact molarity from titration results. Discuss primary standard requirements.

Burettes, Pipettes, 0.1M NaOH, 0.1M HCl, Phenolphthalein indicator, Conical flasks
Burettes, Pipettes, 0.1M H₂SO₄, 0.1M NaOH, Phenolphthalein, Basicity reference chart
Anhydrous Na₂CO₃, Approximately 0.1M HCl, Methyl orange, Volumetric flasks, Analytical balance
Metal carbonate sample, 0.5M HCl, 0M NaOH, Phenolphthalein, Conical flasks

KLB Secondary Chemistry Form 3, Pages 59-62
KLB Secondary Chemistry Form 3, Pages 65-67

THE MOLE

Redox Titrations - Principles

By the end of the lesson, the learner should be able to:
Explain principles of redox titrations
Identify color changes in redox reactions
Understand self-indicating nature of some redox reactions
Write ionic equations for redox processes

Teacher exposition: Redox titration principles. Demonstrate color changes: MnO₄⁻ (purple) → Mn²⁺ (colorless), Cr₂O₇²⁻ (orange) → Cr³⁺ (green). Discussion: Self-indicating reactions. Write half-equations and overall ionic equations.

Potassium manganate(VII), Potassium dichromate(VI), Iron(II) solutions, Color change charts

KLB Secondary Chemistry Form 3, Pages 68-70

THE MOLE

Redox Titrations - KMnO₄ Standardization
Water of Crystallization Determination

By the end of the lesson, the learner should be able to:
Standardize KMnO₄ solution using iron(II) salt
Calculate molarity from redox titration data
Apply 1:5 mole ratio in calculations
Prepare solutions for redox titrations

Experiment: Standardize KMnO₄ using FeSO₄(NH₄)₂SO₄·6H₂O. Dissolve iron salt in boiled, cooled water. Titrate with KMnO₄ until persistent pink color. Calculate molarity using 5:1 mole ratio.

Iron(II) ammonium sulfate, KMnO₄ solution, Dilute H₂SO₄, Pipettes, Burettes
Hydrated iron(II) salt, Standardized KMnO₄, Dilute H₂SO₄, Analytical balance

KLB Secondary Chemistry Form 3, Pages 70-72

THE MOLE

Atomicity and Molar Gas Volume

By the end of the lesson, the learner should be able to:
Define atomicity of gaseous elements
Classify gases as monoatomic, diatomic, or triatomic
Determine molar gas volume experimentally
Calculate gas densities and molar masses

Experiment: Measure volumes and masses of different gases (O₂, CO₂, Cl₂). Calculate densities and molar masses. Determine volume occupied by one mole. Compare values at different conditions.

Gas syringes (50cm³), Various gases, Analytical balance, Gas supply apparatus

KLB Secondary Chemistry Form 3, Pages 73-75

THE MOLE
ORGANIC CHEMISTRY I

Combining Volumes of Gases - Experimental Investigation
Gas Laws and Chemical Equations
Introduction to Organic Chemistry and Hydrocarbons
Sources of Alkanes - Natural Gas, Biogas, and Crude Oil

By the end of the lesson, the learner should be able to:
Investigate Gay-Lussac's law experimentally
Measure combining volumes of reacting gases
Determine simple whole number ratios
Write equations from volume relationships
Define organic chemistry and hydrocarbons
Explain why carbon forms many compounds
Classify hydrocarbons into alkanes, alkenes, and alkynes
Identify the bonding in carbon compounds

Experiment: React NH₃ and HCl gases in measured volumes. Observe formation of NH₄Cl solid. Measure residual gas volumes. Determine combining ratios. Apply to other gas reactions.
Teacher exposition: Definition of organic chemistry. Discussion: Unique properties of carbon - tetravalency, catenation, multiple bonding. Q/A: Examples of hydrocarbons in daily life. Introduction to three main groups of hydrocarbons.

Gas syringes, Dry NH₃ generator, Dry HCl generator, Glass connecting tubes, Clips
Scientific calculators, Gas law charts, Volume ratio examples
Carbon models, Hydrocarbon structure charts, Molecular model kits
Biogas digester model/diagram, Natural gas composition charts, Organic waste samples

KLB Secondary Chemistry Form 3, Pages 75-77
KLB Secondary Chemistry Form 3, Pages 86-87

ORGANIC CHEMISTRY I

Fractional Distillation of Crude Oil

By the end of the lesson, the learner should be able to:
Explain fractional distillation process
Perform fractional distillation of crude oil
Identify different fractions and their uses
Relate boiling points to molecular size

Experiment: Fractional distillation of crude oil using improvised column. Collect fractions at different temperatures (120°C intervals up to 350°C). Test fractions for appearance, flammability, and viscosity. Record observations and relate to molecular size.

Crude oil sample, Boiling tubes, High-temperature thermometer, Sand/porcelain chips, Bunsen burner, Test tubes

KLB Secondary Chemistry Form 3, Pages 87-89

ORGANIC CHEMISTRY I

Cracking of Alkanes - Thermal and Catalytic Methods
Alkane Series and Homologous Series Concept

By the end of the lesson, the learner should be able to:
Define cracking of alkanes
Distinguish between thermal and catalytic cracking
Write equations for cracking reactions
Explain industrial importance of cracking

Teacher exposition: Definition and purpose of cracking. Discussion: Thermal vs catalytic cracking conditions. Worked examples: Cracking equations producing smaller alkanes, alkenes, and hydrogen. Q/A: Industrial applications and hydrogen production.

Cracking process diagrams, Chemical equation charts, Catalyst samples for demonstration
Alkane series chart, Molecular formula worksheets, Periodic table

KLB Secondary Chemistry Form 3, Pages 89-90

ORGANIC CHEMISTRY I

Nomenclature of Alkanes - Straight Chain and Branched

By the end of the lesson, the learner should be able to:
Name straight-chain alkanes using IUPAC rules
Identify parent chains in branched alkanes
Name branched alkanes with substituent groups
Apply systematic naming rules correctly

Teacher demonstration: Step-by-step naming of branched alkanes. Rules application: Longest chain identification, numbering from nearest branch, substituent naming. Practice exercises: Various branched alkane structures. Group work: Name complex branched alkanes.

Structural formula charts, IUPAC naming rules poster, Molecular model kits

KLB Secondary Chemistry Form 3, Pages 90-92

ORGANIC CHEMISTRY I

Isomerism in Alkanes - Structural Isomers
Laboratory Preparation of Methane
Laboratory Preparation of Ethane
Physical Properties of Alkanes

By the end of the lesson, the learner should be able to:
Define isomerism in alkanes
Draw structural isomers of butane and pentane
Distinguish between chain and positional isomerism
Predict number of isomers for given alkanes
Prepare ethane using sodium propanoate and soda lime
Compare preparation methods of methane and ethane
Test properties of ethane gas
Write general equation for alkane preparation

Teacher exposition: Isomerism definition and types. Practical exercise: Draw all isomers of butane and pentane. Discussion: Physical property differences between isomers. Model building: Use molecular models to show isomeric structures.
Experiment: Prepare ethane from sodium propanoate and soda lime. Compare with methane preparation method. Carry out similar tests as for methane. Discussion: General pattern for alkane preparation from sodium alkanoates.

Molecular model kits, Isomerism charts, Structural formula worksheets
Sodium ethanoate, Soda lime, Round-bottomed flask, Gas collection apparatus, Bromine water, Wooden splints
Sodium propanoate, Soda lime, Gas collection apparatus, Testing materials
Physical properties data tables, Graph paper, Calculators, Solubility demonstration materials

KLB Secondary Chemistry Form 3, Pages 92-94
KLB Secondary Chemistry Form 3, Pages 94-96

ORGANIC CHEMISTRY I

Chemical Properties of Alkanes - Combustion and Substitution

By the end of the lesson, the learner should be able to:
Write equations for complete and incomplete combustion
Explain substitution reactions with halogens
Describe conditions for halogenation reactions
Name halogenated alkane products

Worked examples: Combustion equations for various alkanes. Teacher demonstration: Methane + bromine in sunlight (or simulation). Discussion: Free radical mechanism in substitution. Practice: Write equations for chlorination of methane.

Molecular models, Halogenation reaction charts, Chemical equation worksheets

KLB Secondary Chemistry Form 3, Pages 97-98

ORGANIC CHEMISTRY I

Uses of Alkanes in Industry and Daily Life
Introduction to Alkenes and Functional Groups

By the end of the lesson, the learner should be able to:
List major uses of different alkanes
Explain industrial applications of alkanes
Describe environmental considerations
Evaluate economic importance of alkanes

Discussion: Uses of gaseous alkanes as fuels. Teacher exposition: Industrial applications - carbon black, methanol production, hydrogen source. Q/A: Environmental impact and cleaner fuel initiatives. Assignment: Research local uses of alkane products.

Industrial application charts, Product samples, Environmental impact materials
Alkene series charts, Molecular models showing double bonds, Functional group posters

KLB Secondary Chemistry Form 3, Pages 98-100

ORGANIC CHEMISTRY I

Nomenclature of Alkenes

By the end of the lesson, the learner should be able to:
Apply IUPAC rules for naming alkenes
Number carbon chains to give lowest numbers to double bonds
Name branched alkenes with substituents
Distinguish position isomers of alkenes

Teacher demonstration: Step-by-step naming of alkenes. Rules application: Longest chain with double bond, numbering from end nearest double bond. Practice exercises: Name various alkene structures. Group work: Complex branched alkenes with substituents.

IUPAC naming charts for alkenes, Structural formula worksheets, Molecular model kits

KLB Secondary Chemistry Form 3, Pages 101-102

ORGANIC CHEMISTRY I

Isomerism in Alkenes - Branching and Positional
Laboratory Preparation of Ethene
Alternative Preparation of Ethene and Physical Properties
Chemical Properties of Alkenes - Addition Reactions

By the end of the lesson, the learner should be able to:
Draw structural isomers of alkenes
Distinguish between branching and positional isomerism
Identify geometric isomers in alkenes
Predict isomer numbers for given molecular formulas
Describe catalytic dehydration using aluminum oxide
Compare different preparation methods
List physical properties of ethene
Explain trends in alkene physical properties

Practical exercise: Draw all isomers of butene and pentene. Teacher exposition: Branching vs positional isomerism in alkenes. Model building: Use molecular models for isomer visualization. Discussion: Geometric isomerism introduction (basic level).
Demonstration: Alternative method using Al₂O₃ catalyst. Comparison: Acid vs catalytic dehydration methods. Data analysis: Physical properties of alkenes table. Discussion: Property trends with increasing molecular size.

Molecular model kits, Isomerism worksheets, Geometric isomer models
Ethanol, Concentrated H₂SO₄, Round-bottomed flask, Sand bath, Gas collection apparatus, Testing solutions
Aluminum oxide catalyst, Glass wool, Alternative apparatus setup, Physical properties charts
Addition reaction charts, Mechanism diagrams, Chemical equation worksheets

KLB Secondary Chemistry Form 3, Pages 102
KLB Secondary Chemistry Form 3, Pages 102-104

ORGANIC CHEMISTRY I

Oxidation Reactions of Alkenes and Polymerization

By the end of the lesson, the learner should be able to:
Describe oxidation by KMnO₄ and K₂Cr₂O₇
Explain polymerization of ethene
Define monomers and polymers
Write equations for polymer formation

Demonstration: Decolorization of KMnO₄ by alkenes. Teacher exposition: Polymerization process and polymer formation. Examples: Ethene → polyethene formation. Discussion: Industrial importance of polymerization. Practice: Write polymerization equations.

Oxidizing agents for demonstration, Polymer samples, Polymerization charts, Monomer-polymer models

KLB Secondary Chemistry Form 3, Pages 107-108

ORGANIC CHEMISTRY I

Tests for Alkenes and Uses
Introduction to Alkynes and Triple Bond

By the end of the lesson, the learner should be able to:
Perform chemical tests to identify alkenes
Use bromine water and KMnO₄ as test reagents
List industrial and domestic uses of alkenes
Explain importance in plastic manufacture

Practical session: Test known alkenes with bromine water and acidified KMnO₄. Observe rapid decolorization compared to alkanes. Discussion: Uses in plastics, ethanol production, fruit ripening, detergents. Assignment: Research alkene applications.

Test alkenes, Bromine water, Acidified KMnO₄, Plastic samples, Uses reference charts
Alkyne series charts, Triple bond molecular models, Unsaturation comparison charts

KLB Secondary Chemistry Form 3, Pages 108-109

ORGANIC CHEMISTRY I

Nomenclature and Isomerism in Alkynes

By the end of the lesson, the learner should be able to:
Apply IUPAC naming rules for alkynes
Name branched alkynes with substituents
Draw structural isomers of alkynes
Identify branching and positional isomerism

Teacher demonstration: Systematic naming of alkynes using -yne suffix. Practice exercises: Name various alkyne structures. Drawing exercise: Isomers of pentyne and hexyne. Group work: Complex branched alkynes with multiple substituents.

IUPAC naming rules for alkynes, Structural formula worksheets, Molecular model kits

KLB Secondary Chemistry Form 3, Pages 110-111

ORGANIC CHEMISTRY I

Laboratory Preparation of Ethyne
Physical and Chemical Properties of Alkynes
Addition Reactions of Alkynes and Chemical Tests
Uses of Alkynes and Industrial Applications

By the end of the lesson, the learner should be able to:
Prepare ethyne from calcium carbide and water
Set up gas collection apparatus safely
Test physical and chemical properties of ethyne
Write equation for ethyne preparation
Write equations for halogenation of alkynes
Describe hydrogenation and hydrohalogenation
Compare reaction rates: alkynes vs alkenes
Perform chemical tests for alkynes

Experiment: Calcium carbide + water reaction. Use sand layer for heat absorption. Collect ethyne over water. Tests: Color, smell, combustion, bromine water, acidified KMnO₄. Safety: Dry apparatus, controlled water addition.
Worked examples: Two-step addition reactions of ethyne with Br₂, Cl₂, H₂. Discussion: Faster reaction rates in alkynes compared to alkenes. Practical session: Test alkynes with oxidizing agents. Comparison: Rate of decolorization vs alkenes.

Calcium carbide, Sand, Flat-bottomed flask, Dropping funnel, Gas collection apparatus, Testing solutions
Physical properties charts, Comparison tables, Combustion equation examples
Addition reaction charts, Chemical equation worksheets, Test solutions, Stopwatch for rate comparison
Industrial application charts, Welding equipment demonstration/video, Synthetic fiber samples

KLB Secondary Chemistry Form 3, Pages 111-112
KLB Secondary Chemistry Form 3, Pages 113-115

CHLORINE AND ITS COMPOUNDS

Introduction and Preparation of Chlorine
Physical Properties of Chlorine
Chemical Properties of Chlorine - Reaction with Water

By the end of the lesson, the learner should be able to:
Define chlorine and state its position in the periodic table. Describe the occurrence of chlorine in nature. Describe laboratory preparation of chlorine gas. Write balanced equations for chlorine preparation.

Q/A: Review Group VII elements and electron configuration of chlorine ( 8.7). Discussion: Occurrence as sodium chloride in sea water and rock salt. Practical work: Experiment 6.1 - Preparation using MnO2 + concentrated HCl. Setup apparatus as in Figure 6. Safety precautions for handling chlorine gas.

Manganese(IV) oxide, Concentrated HCl, Gas collection apparatus, Water, Concentrated H2SO4, Blue litmus paper, Gas jars
Preserved chlorine gas, Water trough, Gas jars, Observation tables, Safety equipment
Chlorine gas, Distilled water, Blue and red litmus papers, Colored flower petals, Gas jars, Boiling tubes

KLB Secondary Chemistry Form 4, Pages 195-196

CHLORINE AND ITS COMPOUNDS

Chemical Properties of Chlorine - Reaction with Metals
Chemical Properties of Chlorine - Reaction with Non-metals
Oxidising Properties of Chlorine

By the end of the lesson, the learner should be able to:
Investigate reactions of chlorine with metals. Write balanced equations for metal-chlorine reactions. Explain the formation of metal chlorides. Demonstrate exothermic nature of these reactions.

Practical work: Experiment 6.4 - Reactions with burning magnesium, hot iron wire, dry chlorine over hot iron coil (Figure 6.2). Recording observations in Table 6. Observations: White fumes (MgCl2), glowing iron wire, black crystals (FeCl3). Discussion: Formation of higher oxidation state chlorides. Safety: Proper ventilation and eye protection.

Magnesium ribbon, Iron wire, Chlorine gas, Deflagrating spoon, Combustion tube, Anhydrous CaCl2, Gas jars
Red phosphorus, Hydrogen gas, Chlorine gas, Deflagrating spoon, Gas jars, Bunsen burner, Safety equipment
Sodium sulphite solution, Barium nitrate, Lead nitrate, Hydrogen sulphide gas, Aqueous ammonia, Chlorine gas, Test tubes

KLB Secondary Chemistry Form 4, Pages 199-201

CHLORINE AND ITS COMPOUNDS

Reaction of Chlorine with Alkali Solutions
Oxidising Properties - Displacement Reactions
Test for Chloride Ions

By the end of the lesson, the learner should be able to:
Investigate reactions of chlorine with alkalis. Compare reactions with cold dilute and hot concentrated alkalis. Write equations for formation of chlorates and hypochlorites. Explain formation of bleaching powder.

Practical work: Experiment 6.7 - Bubbling chlorine through cold dilute NaOH and hot concentrated NaOH. Recording observations in Table 6. Formation of pale-yellow solution (cold) vs colorless solution (hot). Equations: 3Cl2 + 6NaOH → 5NaCl + NaClO3 + 3H2O (hot), Cl2 + 2NaOH → NaCl + NaClO + H2O (cold). Discussion: Industrial production of bleaching powder.

Sodium hydroxide solutions (dilute cold, concentrated hot), Chlorine gas, Beakers, Bunsen burner, Thermometer
Potassium bromide solution, Potassium iodide solution, Chlorine gas, Test tubes, Observation charts
Sodium chloride, Concentrated H2SO4, Lead(II) nitrate solution, Aqueous ammonia, Glass rod, Test tubes, Bunsen burner

KLB Secondary Chemistry Form 4, Pages 202-203

CHLORINE AND ITS COMPOUNDS

Uses of Chlorine and its Compounds
Hydrogen Chloride - Laboratory Preparation
Chemical Properties of Hydrogen Chloride

By the end of the lesson, the learner should be able to:
List the industrial uses of chlorine. Explain the use of chlorine in water treatment. Describe manufacture of chlorine compounds. Relate properties to uses of chlorine.
Describe laboratory preparation of hydrogen chloride gas. Set up apparatus for HCl preparation. Investigate physical properties of HCl gas. Explain the method of collection used.

Discussion: Industrial applications - HCl manufacture, bleaching agents for cotton and paper industries, water treatment and sewage plants. Study Figure 6.3(a) - bleaching chemicals. Applications: Chloroform (anaesthetic), solvents (trichloroethane), CFCs, PVC plastics, pesticides (DDT), germicides and fungicides. Q/A: Relating chemical properties to practical applications.
Practical work: Experiment 6.10 - Preparation using rock salt (NaCl) + concentrated H2SO Setup apparatus as in Figure 6.3(b). Testing physical properties and recording in Table 6.6. Tests: Solubility (fountain experiment), reaction with ammonia, effect on litmus. Collection by downward delivery due to density. Writing equation: NaCl + H2SO4 → NaHSO4 + HCl.

Charts showing industrial uses, Samples of bleaching agents, PVC materials, Photographs of water treatment plants, Industrial application diagrams
Rock salt (NaCl), Concentrated H2SO4, Gas collection apparatus, Ammonia solution, Litmus papers, Water trough, Gas jars
Distilled water, Filter funnel, Metals (Zn, Fe, Mg, Cu), NaOH solution, Carbonates, Lead nitrate, Methylbenzene, Indicators

KLB Secondary Chemistry Form 4, Pages 205-207
KLB Secondary Chemistry Form 4, Pages 207-208

CHLORINE AND ITS COMPOUNDS

Large-scale Manufacture of Hydrochloric Acid
Uses of Hydrochloric Acid

By the end of the lesson, the learner should be able to:
Describe industrial production of hydrochloric acid. Identify raw materials and conditions used. Explain the controlled combustion process. Draw flow diagrams of the industrial process.

Study of Figure 6.4 - Large-scale manufacture setup. Discussion: Raw materials (H2 from electrolysis/cracking, Cl2 from electrolysis). Controlled combustion: H2 + Cl2 → 2HCl in jet burner. Dissolving HCl gas in water over glass beads. Safety: Explosive nature of H2/Cl2 mixture, use of excess chlorine. Industrial considerations: 35% concentration, transport in rubber-lined steel tanks.

Flow diagrams, Industrial photographs, Glass beads samples, Charts showing electrolysis processes, Safety equipment models
Samples of rusted and cleaned metals, Photographic materials, pH control charts, Industrial application videos, Water treatment diagrams

KLB Secondary Chemistry Form 4, Pages 211-212

CHLORINE AND ITS COMPOUNDS

Environmental Pollution by Chlorine Compounds and Summary

By the end of the lesson, the learner should be able to:
Explain environmental effects of chlorine compounds. Describe the impact of CFCs on ozone layer. Discuss pollution by chlorine-containing pesticides. Summarize key concepts of chlorine chemistry.

Discussion: Environmental impacts - chlorine gas forming acid rain, CFCs (life span CCl3F = 75 years, CCl2F2 = 110 years) breaking down ozone layer. DDT as persistent pesticide, PVC as non-biodegradable plastic. NEMA role in environmental protection, Stockholm Convention on DDT. Control measures and alternatives. Revision: Key reactions, properties, uses, and environmental considerations. Summary of halogen chemistry concepts.

Environmental pollution charts, Ozone layer diagrams, DDT restriction documents, PVC waste samples, NEMA guidelines, Summary charts of reactions

KLB Secondary Chemistry Form 4, Pages 213-215