NITROGEN AND ITS COMPOUNDS

Introduction to Nitrogen - Properties and Occurrence

By the end of the lesson, the learner should be able to:
Describe position of nitrogen in the periodic table
State electron configuration of nitrogen
Identify natural occurrence of nitrogen
Explain why nitrogen exists as diatomic molecules

In groups, learners are guided to:
Teacher exposition: Nitrogen as Group V element, atomic number 7, electron arrangement Discussion: 78% of atmosphere is nitrogen. Q/A: Combined nitrogen in compounds - nitrates, proteins. Explanation: N≡N triple bond strength.

Periodic table charts, Atmospheric composition diagrams, Molecular models showing N≡N triple bond

KLB Secondary Chemistry Form 3, Pages 119

NITROGEN AND ITS COMPOUNDS

Isolation of Nitrogen from Air - Industrial and Laboratory Methods
Laboratory Preparation of Nitrogen Gas
Properties and Uses of Nitrogen Gas

By the end of the lesson, the learner should be able to:
Describe isolation of nitrogen from air
Explain fractional distillation of liquid air
Set up apparatus for laboratory isolation
Identify impurities removed during isolation
Describe physical properties of nitrogen
Explain chemical inertness of nitrogen
Describe reactions at high temperatures
List industrial uses of nitrogen

In groups, learners are guided to:
Experiment: Laboratory isolation using aspirator. Pass air through KOH solution to remove CO₂, then over heated copper to remove oxygen. Teacher demonstration: Fractional distillation principles. Flow chart study: Industrial nitrogen production steps.
Analysis of test results: Colorless, odorless, does not burn or support combustion. Discussion: Triple bond strength and chemical inertness. High temperature reactions with metals forming nitrides. Uses: Haber process, light bulbs, refrigerant, inert atmosphere.

Aspirator, KOH solution, Copper turnings, Heating apparatus, Fractional distillation flow chart
Sodium nitrite, Ammonium chloride, Round-bottomed flask, Gas collection apparatus, Test reagents, Deflagrating spoon
Property summary charts, Uses of nitrogen displays, Industrial application diagrams

KLB Secondary Chemistry Form 3, Pages 119-121
KLB Secondary Chemistry Form 3, Pages 121-123

NITROGEN AND ITS COMPOUNDS

Nitrogen(I) Oxide - Preparation and Properties

By the end of the lesson, the learner should be able to:
Prepare nitrogen(I) oxide from ammonium nitrate
Test physical and chemical properties
Explain decomposition and oxidizing properties
Describe uses of nitrogen(I) oxide

In groups, learners are guided to:
Experiment: Heat ammonium nitrate carefully in test tube. Collect gas over warm water. Tests: Color, smell, glowing splint test, reaction with heated copper and sulfur. Safety: Stop heating while some solid remains to avoid explosion.

Ammonium nitrate, Test tubes, Gas collection apparatus, Copper turnings, Sulfur, Glowing splints

KLB Secondary Chemistry Form 3, Pages 123-125

NITROGEN AND ITS COMPOUNDS

Nitrogen(II) Oxide - Preparation and Properties
Nitrogen(IV) Oxide - Preparation and Properties

By the end of the lesson, the learner should be able to:
Prepare nitrogen(II) oxide from copper and dilute nitric acid
Observe colorless gas and brown fumes formation
Test reactions with air and iron(II) sulfate
Explain oxidation in air to NO₂

In groups, learners are guided to:
Experiment: Add dilute HNO₃ to copper turnings. Observe brown fumes formation then disappearance. Tests: Effect on litmus, burning splint, FeSO₄ complex formation. Discussion: NO oxidation to NO₂ in air.

Copper turnings, Dilute nitric acid, Gas collection apparatus, Iron(II) sulfate solution, Test reagents
Copper turnings, Concentrated nitric acid, Lead(II) nitrate, Gas collection apparatus, U-tube with ice, Testing materials

KLB Secondary Chemistry Form 3, Pages 125-127

NITROGEN AND ITS COMPOUNDS

Comparison of Nitrogen Oxides and Environmental Effects

By the end of the lesson, the learner should be able to:
Compare preparation methods of nitrogen oxides
Distinguish between different nitrogen oxides
Explain formation in vehicle engines
Describe environmental pollution effects

In groups, learners are guided to:
Comparative study: Properties table of N₂O, NO, NO₂. Discussion: Formation in internal combustion engines. Environmental effects: Acid rain formation, smog, health problems. Worked examples: Distinguishing tests for each oxide.

Comparison charts, Environmental impact diagrams, Vehicle emission illustrations

KLB Secondary Chemistry Form 3, Pages 123-131

NITROGEN AND ITS COMPOUNDS

Laboratory Preparation of Ammonia
Preparation of Aqueous Ammonia and Solubility

By the end of the lesson, the learner should be able to:
Prepare ammonia from ammonium salts and alkalis
Set up apparatus with proper gas collection
Test characteristic properties of ammonia
Explain displacement reaction principle
Prepare aqueous ammonia solution
Demonstrate high solubility using fountain experiment
Explain alkaline properties of aqueous ammonia
Write equations for ammonia in water

In groups, learners are guided to:
Experiment: Heat mixture of calcium hydroxide and ammonium chloride. Collect gas by upward delivery using calcium oxide as drying agent. Tests: Color, smell, combustion, HCl fumes test, litmus paper. Safety: Slanted flask position.
Experiment: Dissolve ammonia in water using inverted funnel method. Fountain experiment: Show partial vacuum formation due to high solubility. Tests: Effect on universal indicator, pH measurement. Theory: NH₃ + H₂O equilibrium.

Calcium hydroxide, Ammonium chloride, Round-bottomed flask, Calcium oxide, HCl solution, Glass rod, Litmus paper
Ammonia generation apparatus, Funnel, Universal indicator, Fountain apparatus, pH meter/paper

KLB Secondary Chemistry Form 3, Pages 131-134
KLB Secondary Chemistry Form 3, Pages 134-136

NITROGEN AND ITS COMPOUNDS

Reactions of Aqueous Ammonia with Metal Ions
Chemical Properties of Ammonia - Reactions with Acids and Combustion

By the end of the lesson, the learner should be able to:
Test reactions of aqueous ammonia with various metal ions
Observe precipitate formation and dissolution
Explain complex ion formation
Use reactions for metal ion identification

In groups, learners are guided to:
Experiment: Add aqueous ammonia dropwise to solutions of Ca²⁺, Mg²⁺, Al³⁺, Zn²⁺, Fe²⁺, Fe³⁺, Pb²⁺, Cu²⁺. Record observations with few drops vs excess ammonia. Identify complex ion formation with Zn²⁺ and Cu²⁺.

Various metal salt solutions, Aqueous ammonia, Test tubes, Droppers, Observation recording tables
Various dilute acids, Methyl orange, Oxygen supply, Platinum wire, Copper(II) oxide, Combustion apparatus, U-tube for collection

KLB Secondary Chemistry Form 3, Pages 136-138

NITROGEN AND ITS COMPOUNDS

Industrial Manufacture of Ammonia - The Haber Process

By the end of the lesson, the learner should be able to:
Describe raw materials and their sources
Explain optimum conditions for ammonia synthesis
Draw flow diagram of Haber process
Explain economic considerations and catalyst use

In groups, learners are guided to:
Teacher exposition: N₂ from air, H₂ from natural gas/cracking. Process conditions: 500°C, 200 atm, iron catalyst. Flow diagram study: Purification, compression, catalytic chamber, separation, recycling. Economic factors: Compromise between yield and rate.

Haber process flow charts, Industrial diagrams, Catalyst samples, Economic analysis sheets

KLB Secondary Chemistry Form 3, Pages 140-141

NITROGEN AND ITS COMPOUNDS

Uses of Ammonia and Introduction to Nitrogenous Fertilizers

By the end of the lesson, the learner should be able to:
List major uses of ammonia
Explain importance as fertilizer
Calculate nitrogen percentages in fertilizers
Compare different nitrogenous fertilizers

In groups, learners are guided to:
Discussion: Uses - fertilizer, refrigerant, cleaning agent, hydrazine production. Introduction to fertilizers: Ammonium sulfate, ammonium nitrate, ammonium phosphate, urea, CAN. Calculations: Percentage nitrogen content in each fertilizer type.

Fertilizer samples, Percentage calculation worksheets, Use application charts, Calculator

KLB Secondary Chemistry Form 3, Pages 141-144

NITROGEN AND ITS COMPOUNDS

Nitrogenous Fertilizers - Types and Calculations
Laboratory Preparation of Nitric(V) Acid
Industrial Manufacture of Nitric(V) Acid

By the end of the lesson, the learner should be able to:
Calculate percentage nitrogen in various fertilizers
Compare fertilizer effectiveness
Prepare simple nitrogenous fertilizers
Discuss environmental considerations
Describe catalytic oxidation process
Explain raw materials and conditions
Draw flow diagram of industrial process
Calculate theoretical yields and efficiency

In groups, learners are guided to:
Worked examples: Calculate % N in (NH₄)₂SO₄, NH₄NO₃, (NH₄)₃PO₄, CO(NH₂)₂, CAN. Comparison: Urea has highest nitrogen content. Practical: Prepare ammonium sulfate from ammonia and sulfuric acid. Environmental impact discussion.
Teacher exposition: Ostwald process - NH₃ oxidation with Pt-Rh catalyst at 900°C. Flow diagram: Oxidation chamber, cooling, absorption tower. Equations: NH₃ → NO → NO₂ → HNO₃. Economic factors: Catalyst cost, heat recovery.

Various fertilizer formulas, Scientific calculators, Laboratory preparation materials, Environmental impact data
Potassium nitrate, Concentrated sulfuric acid, All-glass apparatus, Condenser, Retort stand, Safety equipment
Industrial process flow charts, Catalyst samples, Process condition charts, Efficiency calculation sheets

KLB Secondary Chemistry Form 3, Pages 141-144
KLB Secondary Chemistry Form 3, Pages 145-147

NITROGEN AND ITS COMPOUNDS

Reactions of Dilute Nitric(V) Acid with Metals

By the end of the lesson, the learner should be able to:
Test reactions with various metals
Explain absence of hydrogen gas production
Observe formation of nitrogen oxides
Write equations for metal-acid reactions

In groups, learners are guided to:
Experiment: Add dilute HNO₃ to Mg, Zn, Cu. Test gases produced with burning splint. Observe that no H₂ is produced (except with Mg in very dilute acid). Explain oxidation of any H₂ formed to water. Record observations and write equations.

Various metals (Mg, Zn, Cu), Dilute nitric acid, Test tubes, Gas testing apparatus, Burning splints

KLB Secondary Chemistry Form 3, Pages 147-150

NITROGEN AND ITS COMPOUNDS

Reactions of Dilute Nitric(V) Acid with Carbonates and Hydroxides

By the end of the lesson, the learner should be able to:
Test reactions with carbonates and hydrogen carbonates
Test neutralization with metal hydroxides and oxides
Identify products formed
Write balanced chemical equations

In groups, learners are guided to:
Experiments: (a) Add dilute HNO₃ to Na₂CO₃, CaCO₃, ZnCO₃, CuCO₃, NaHCO₃. Test gas evolved with lime water. (b) Neutralize NaOH, CaO, CuO, PbO with dilute HNO₃. Record color changes and write equations.

Various carbonates and hydroxides, Dilute nitric acid, Lime water, Universal indicator, Test tubes

KLB Secondary Chemistry Form 3, Pages 147-150

NITROGEN AND ITS COMPOUNDS
SULPHUR AND ITS COMPOUNDS
SULPHUR AND ITS COMPOUNDS

Reactions of Concentrated Nitric(V) Acid - Oxidizing Properties
Extraction of Sulphur
Allotropes of Sulphur

By the end of the lesson, the learner should be able to:
Demonstrate strong oxidizing properties
Test reactions with FeSO₄, sulfur, and copper
Observe formation of nitrogen dioxide
Explain electron transfer in oxidation

In groups, learners are guided to:
Experiments: (a) Add concentrated HNO₃ to acidified FeSO₄ - observe color change. (b) Add to sulfur - observe reaction. (c) Add to copper turnings - observe vigorous reaction and brown fumes. Explain oxidizing power and reduction to NO₂.

Concentrated nitric acid, Iron(II) sulfate, Sulfur powder, Copper turnings, Test tubes, Fume cupboard access
Charts showing periodic table, Diagram of Frasch process, Samples of sulphur compounds (pyrites, gypsum)
Powdered sulphur, Carbon(IV) sulphide, Evaporating dish, Glass rod, Hand lens, Boiling tubes, Filter paper, Beakers

KLB Secondary Chemistry Form 3, Pages 150-151

SULPHUR AND ITS COMPOUNDS

Physical Properties of Sulphur - Solubility
Physical Properties of Sulphur - Effect of Heat
Chemical Properties of Sulphur - Reactions with Elements
Chemical Properties of Sulphur - Reactions with Acids
Uses of Sulphur and Introduction to Oxides

By the end of the lesson, the learner should be able to:
Investigate the solubility of sulphur in different solvents. Explain the molecular structure of sulphur. Compare solubility in polar and non-polar solvents. State the physical properties of sulphur.
Investigate the reaction of sulphur with concentrated acids. Identify the products formed in these reactions. Write balanced equations for oxidation reactions. Test for sulphate ions using barium chloride.

In groups, learners are guided to:
Practical work: Experiment 2(a) - Testing solubility of sulphur in water, benzene, methylbenzene, and carbon(IV) sulphide. Observation and recording in Table Discussion: Explain why sulphur dissolves in organic solvents but not water. Drawing: Puckered ring structure of S8 molecule.
Practical work: Experiment 3(b) - Reactions with concentrated nitric(V) acid, sulphuric(VI) acid, and hydrochloric acid. Testing with barium chloride solution. Observation: Formation of sulphate ions, brown fumes, no reaction with HCl. Discussion: Sulphur as a reducing agent, acids as oxidizing agents.

Powdered sulphur, Water, Benzene, Methylbenzene, Carbon(IV) sulphide, Test tubes, Charts showing molecular structure
Powdered sulphur, Test tubes, Bunsen burner, Cold surface for condensation, Thermometer, Safety equipment
Sulphur, Iron powder, Copper powder, Oxygen gas jar, Deflagrating spoon, Moist litmus papers, Test tubes, Bunsen burner
Sulphur powder, Concentrated HNO3, Concentrated H2SO4, Concentrated HCl, Barium chloride solution, Test tubes, Fume cupboard access
Charts showing uses of sulphur, Samples of vulcanized rubber, Fungicides, Industrial photographs, Textbook diagrams

KLB Secondary Chemistry Form 4, Pages 163-164
KLB Secondary Chemistry Form 4, Pages 167-168

SULPHUR AND ITS COMPOUNDS

Preparation of Sulphur(IV) Oxide
Physical and Chemical Properties of Sulphur(IV) Oxide

By the end of the lesson, the learner should be able to:
Describe laboratory preparation of sulphur(IV) oxide. Set up apparatus for gas preparation and collection. Write balanced equations for the preparation reactions. Explain the drying and collection methods used.

In groups, learners are guided to:
Practical work: Experiment 4 - Preparation of SO2 using sodium sulphite and dilute HCl. Apparatus setup: Round-bottomed flask, delivery tube, gas jars. Collection: Downward delivery method. Testing: Using acidified potassium chromate(VI) paper. Alternative method: Copper + concentrated H2SO

Sodium sulphite, Dilute HCl, Round-bottomed flask, Delivery tubes, Gas jars, Concentrated H2SO4 for drying, Acidified potassium chromate(VI) paper
SO2 gas from previous preparation, Litmus papers, Universal indicator, 0.1M NaOH solution, Water, Test tubes, Safety equipment

KLB Secondary Chemistry Form 4, Pages 170-171

SULPHUR AND ITS COMPOUNDS

Bleaching Action of Sulphur(IV) Oxide

By the end of the lesson, the learner should be able to:
Investigate the bleaching properties of SO Compare SO2 bleaching with chlorine bleaching. Explain the mechanism of SO2 bleaching. Relate bleaching to paper manufacturing.

In groups, learners are guided to:
Practical work: Experiment 6 - Placing colored flower petals in SO2 gas. Observation: Temporary bleaching effect. Discussion: SO2 + H2O → H2SO3, reduction of organic dyes. Comparison: Permanent vs temporary bleaching. Application: Paper industry bleaching processes.

Colored flower petals (red/blue), SO2 gas jars, Hand lens for observation, Charts comparing bleaching agents

KLB Secondary Chemistry Form 4, Pages 173

SULPHUR AND ITS COMPOUNDS

Reducing Action of Sulphur(IV) Oxide
Oxidising Action of Sulphur(IV) Oxide

By the end of the lesson, the learner should be able to:
Investigate SO2 as a reducing agent. Test reactions with various oxidizing agents. Write ionic equations for redox reactions. Identify color changes in redox reactions.

In groups, learners are guided to:
Practical work: Experiment 7 - Testing SO2 with acidified potassium dichromate(VI), potassium manganate(VII), bromine water, iron(III) chloride. Recording observations in Table 6. Color changes: Orange to green, purple to colorless, brown to colorless, yellow to pale green. Writing half-equations and overall equations.

SO2 gas, Acidified K2Cr2O7, Acidified KMnO4, Bromine water, Iron(III) chloride solution, Concentrated HNO3, Test tubes
SO2 gas jars, Magnesium ribbon, Deflagrating spoon, Hydrogen sulphide gas, Water droppers, Safety equipment

KLB Secondary Chemistry Form 4, Pages 173-176

SULPHUR AND ITS COMPOUNDS

Test for Sulphate and Sulphite Ions & Uses of SO2
Large-scale Manufacture of Sulphuric(VI) Acid - Contact Process

By the end of the lesson, the learner should be able to:
Carry out confirmatory tests for sulphate and sulphite ions. Distinguish between sulphate and sulphite using chemical tests. List the uses of sulphur(IV) oxide. Explain the applications in industry.
Describe the contact process for manufacturing H2SO Identify raw materials and conditions used. Explain the role of catalyst in the process. Draw flow diagrams of the contact process.

In groups, learners are guided to:
Practical work: Experiment 9 - Testing sodium sulphate and sodium sulphite with barium chloride. Adding dilute HCl to precipitates. Recording observations in Table 8. Discussion: BaSO4 insoluble in acid, BaSO3 dissolves. Uses: Raw material for H2SO4, bleaching wood pulp, fumigant, preservative.
Study of flow diagram: Figure 12 - Contact process. Discussion: Raw materials (sulphur, air), burning sulphur to SO Purification: Electrostatic precipitation, drying with H2SO Catalytic chamber: V2O5 catalyst at 450°C, 2-3 atmospheres. Formation of oleum: H2S2O7. Safety and environmental considerations.

Sodium sulphate solution, Sodium sulphite solution, Barium chloride solution, Dilute HCl, Test tubes, Charts showing industrial uses
Flow chart diagrams, Charts showing industrial plant, Samples of catalyst (V2O5), Photographs of Thika chemical plant, Calculator for percentage calculations

KLB Secondary Chemistry Form 4, Pages 178-179
KLB Secondary Chemistry Form 4, Pages 179-181

SULPHUR AND ITS COMPOUNDS

Properties of Concentrated Sulphuric(VI) Acid - Dehydrating Properties
Properties of Concentrated Sulphuric(VI) Acid - Oxidizing Properties

By the end of the lesson, the learner should be able to:
Investigate the dehydrating properties of concentrated H2SO Demonstrate removal of water from hydrated salts. Show dehydration of organic compounds. Explain the hygroscopic nature of the acid.

In groups, learners are guided to:
Practical work: Experiment 10 - Adding concentrated H2SO4 to copper(II) sulphate crystals, sucrose crystals, ethanol. Observations: Blue to white crystals, charring of sugar, formation of ethene. Safety: Proper dilution technique - acid to water. Testing evolved gases. Discussion: Chemical vs physical dehydration.

Concentrated H2SO4, Copper(II) sulphate crystals, Sucrose, Ethanol, KMnO4 solution, Test tubes, Beakers, Safety equipment, Fume cupboard
Copper foil, Zinc granules, Charcoal powder, Concentrated H2SO4, Acidified K2Cr2O7 paper, Lime water, Test tubes, Bunsen burner

KLB Secondary Chemistry Form 4, Pages 181-183

SULPHUR AND ITS COMPOUNDS

Properties of Concentrated Sulphuric(VI) Acid - Displacement Reactions

By the end of the lesson, the learner should be able to:
Investigate acid displacement reactions. Demonstrate formation of volatile acids. Test the evolved gases for identification. Write equations for displacement reactions.

In groups, learners are guided to:
Practical work: Experiment 10 (continued) - Reactions with potassium nitrate and sodium chloride. Testing evolved gases with moist blue litmus, concentrated ammonia. Observations: Brown fumes (NO2), white fumes (HCl). Discussion: Less volatile acid displacing more volatile acids. Industrial applications.

Potassium nitrate crystals, Sodium chloride crystals, Concentrated H2SO4, Moist blue litmus paper, Concentrated ammonia, Test tubes, Bunsen burner

KLB Secondary Chemistry Form 4, Pages 184

SULPHUR AND ITS COMPOUNDS

Reactions of Dilute Sulphuric(VI) Acid - With Metals

By the end of the lesson, the learner should be able to:
Investigate reactions of dilute H2SO4 with metals. Compare reactivity of different metals. Test for hydrogen gas evolution. Relate reactions to reactivity series.

In groups, learners are guided to:
Practical work: Experiment 11 - Reactions with magnesium, zinc, copper. Testing evolved gas with burning splint. Recording observations in Table 10. Discussion: More reactive metals above hydrogen displace it. Vigour of reaction decreases down reactivity series. Writing ionic equations.

Magnesium ribbon, Zinc granules, Copper turnings, Dilute H2SO4, Test tubes, Burning splints, Reactivity series chart

KLB Secondary Chemistry Form 4, Pages 184-185

SULPHUR AND ITS COMPOUNDS

Reactions of Dilute Sulphuric(VI) Acid - With Carbonates
Reactions of Dilute Sulphuric(VI) Acid - With Oxides and Hydroxides
Hydrogen Sulphide - Preparation and Physical Properties

By the end of the lesson, the learner should be able to:
Investigate reactions of dilute H2SO4 with carbonates. Test for carbon dioxide evolution. Explain why some reactions stop prematurely. Compare reactions of different metal carbonates.
Investigate reactions of dilute H2SO4 with metal oxides and hydroxides. Identify neutralization reactions. Explain formation of insoluble sulphates. Write equations for acid-base reactions.

In groups, learners are guided to:
Practical work: Experiment 12 - Reactions with sodium carbonate, zinc carbonate, calcium carbonate, copper(II) carbonate. Testing evolved gas with lime water. Recording observations in Table 1 Discussion: Formation of insoluble calcium sulphate coating. Effervescence and CO2 identification.
Practical work: Experiment 13 - Reactions with magnesium oxide, zinc oxide, copper(II) oxide, lead(II) oxide, sodium hydroxide. Recording observations in Table 1 Discussion: Salt and water formation, immediate stopping with lead(II) oxide due to insoluble PbSO Acid-base neutralization concept.

Sodium carbonate, Zinc carbonate, Calcium carbonate, Copper(II) carbonate, Dilute H2SO4, Lime water, Test tubes
Metal oxides (MgO, ZnO, CuO, PbO), NaOH solution, 2M H2SO4, Test tubes, Bunsen burner for warming
Iron(II) sulphide, Dilute HCl, Apparatus for gas generation, Anhydrous CaCl2, Gas jars, Safety equipment, Fume cupboard

KLB Secondary Chemistry Form 4, Pages 185-186
KLB Secondary Chemistry Form 4, Pages 186-187

SULPHUR AND ITS COMPOUNDS

Chemical Properties of Hydrogen Sulphide

By the end of the lesson, the learner should be able to:
Investigate H2S as a reducing agent. Test reactions with oxidizing agents. Demonstrate precipitation of metal sulphides. Write ionic equations for redox reactions.

In groups, learners are guided to:
Practical demonstrations: H2S with bromine water, iron(III) chloride, acidified KMnO4, K2Cr2O7. Precipitation tests: H2S with copper(II) sulphate, lead(II) nitrate, zinc sulphate. Color changes: Brown to colorless, yellow to green, purple to colorless. Formation of black, yellow, and white precipitates.

H2S gas, Bromine water, Iron(III) chloride, KMnO4, K2Cr2O7, Metal salt solutions, Test tubes, Droppers

KLB Secondary Chemistry Form 4, Pages 188-190

SULPHUR AND ITS COMPOUNDS

Pollution Effects and Summary

By the end of the lesson, the learner should be able to:
Explain environmental pollution by sulphur compounds. Describe formation and effects of acid rain. Suggest methods to reduce sulphur pollution. Summarize key concepts of sulphur chemistry.

In groups, learners are guided to:
Discussion: Sources of SO2 pollution - burning fossil fuels, metal extraction, H2SO4 manufacture. Formation of acid rain: SO2 + H2O → H2SO3 → H2SO Effects: Plant damage, aquatic life destruction, building corrosion, soil acidification. Control measures: Scrubbing with Ca(OH)2, catalytic converters. Revision: Key reactions, properties, uses.

Charts showing pollution effects, Photographs of acid rain damage, Environmental data, Summary charts of reactions, Industrial pollution control diagrams

KLB Secondary Chemistry Form 4, Pages 190-194

ORGANIC CHEMISTRY I

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:
Define organic chemistry and hydrocarbons
Explain why carbon forms many compounds
Classify hydrocarbons into alkanes, alkenes, and alkynes
Identify the bonding in carbon compounds

In groups, learners are guided to:
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.

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 86-87

ORGANIC CHEMISTRY I

Fractional Distillation of Crude Oil
Cracking of Alkanes - Thermal and Catalytic Methods

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
Define cracking of alkanes
Distinguish between thermal and catalytic cracking
Write equations for cracking reactions
Explain industrial importance of cracking

In groups, learners are guided to:
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.
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.

Crude oil sample, Boiling tubes, High-temperature thermometer, Sand/porcelain chips, Bunsen burner, Test tubes
Cracking process diagrams, Chemical equation charts, Catalyst samples for demonstration

KLB Secondary Chemistry Form 3, Pages 87-89
KLB Secondary Chemistry Form 3, Pages 89-90

ORGANIC CHEMISTRY I

Alkane Series and Homologous Series Concept
Nomenclature of Alkanes - Straight Chain and Branched

By the end of the lesson, the learner should be able to:
Define homologous series using alkanes
Write molecular formulas for first 10 alkanes
Identify characteristics of homologous series
Apply general formula CₙH₂ₙ₊₂ for alkanes

In groups, learners are guided to:
Teacher exposition: Homologous series definition and characteristics. Table completion: Names, molecular formulas, and structures of first 10 alkanes. Discussion: General formula application. Pattern recognition: Gradual change in physical properties.

Alkane series chart, Molecular formula worksheets, Periodic table
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

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

In groups, learners are guided to:
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.

Molecular model kits, Isomerism charts, Structural formula worksheets

KLB Secondary Chemistry Form 3, Pages 92-94

ORGANIC CHEMISTRY I

Laboratory Preparation of Methane

By the end of the lesson, the learner should be able to:
Describe laboratory preparation of methane
Perform methane preparation experiment safely
Test physical and chemical properties of methane
Write equation for methane preparation

In groups, learners are guided to:
Experiment: Heat mixture of sodium ethanoate and soda lime. Collect methane gas over water. Tests: Color, smell, combustion, reaction with bromine in dark. Record observations in table format. Safety precautions during gas collection.

Sodium ethanoate, Soda lime, Round-bottomed flask, Gas collection apparatus, Bromine water, Wooden splints

KLB Secondary Chemistry Form 3, Pages 94-96

ORGANIC CHEMISTRY I

Laboratory Preparation of Ethane
Physical Properties of Alkanes
Chemical Properties of Alkanes - Combustion and Substitution

By the end of the lesson, the learner should be able to:
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
Describe physical properties of alkanes
Explain trends in melting and boiling points
Relate molecular size to physical properties
Compare solubility in different solvents

In groups, learners are guided to:
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.
Data analysis: Study table of physical properties of first 10 alkanes. Graph plotting: Boiling points vs number of carbon atoms. Discussion: Intermolecular forces and property trends. Q/A: Solubility patterns in polar and non-polar solvents.

Sodium propanoate, Soda lime, Gas collection apparatus, Testing materials
Physical properties data tables, Graph paper, Calculators, Solubility demonstration materials
Molecular models, Halogenation reaction charts, Chemical equation worksheets

KLB Secondary Chemistry Form 3, Pages 94-96
KLB Secondary Chemistry Form 3, Pages 96-97

ORGANIC CHEMISTRY I

Uses of Alkanes in Industry and Daily Life

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

In groups, learners are guided to:
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

KLB Secondary Chemistry Form 3, Pages 98-100

ORGANIC CHEMISTRY I

Introduction to Alkenes and Functional Groups

By the end of the lesson, the learner should be able to:
Define alkenes and unsaturation
Identify the C=C functional group
Write general formula for alkenes (CₙH₂ₙ)
Compare alkenes with alkanes

In groups, learners are guided to:
Teacher exposition: Alkenes definition and unsaturation concept. Introduction: C=C double bond as functional group. Table study: First 6 members of alkene series. Comparison: Alkenes vs alkanes - formulas and structures.

Alkene series charts, Molecular models showing double bonds, Functional group posters

KLB Secondary Chemistry Form 3, Pages 100-101

ORGANIC CHEMISTRY I

Nomenclature of Alkenes
Isomerism in Alkenes - Branching and Positional

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

In groups, learners are guided to:
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
Molecular model kits, Isomerism worksheets, Geometric isomer models

KLB Secondary Chemistry Form 3, Pages 101-102

ORGANIC CHEMISTRY I

Laboratory Preparation of Ethene
Alternative Preparation of Ethene and Physical Properties

By the end of the lesson, the learner should be able to:
Prepare ethene by dehydration of ethanol
Describe role of concentrated sulfuric acid
Set up apparatus safely for ethene preparation
Test physical and chemical properties of ethene
Describe catalytic dehydration using aluminum oxide
Compare different preparation methods
List physical properties of ethene
Explain trends in alkene physical properties

In groups, learners are guided to:
Experiment: Dehydration of ethanol using concentrated H₂SO₄ at 170°C. Use sand bath for controlled heating. Pass gas through NaOH to remove impurities. Tests: Bromine water, acidified KMnO₄, combustion. Safety precautions with concentrated acid.
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.

Ethanol, Concentrated H₂SO₄, Round-bottomed flask, Sand bath, Gas collection apparatus, Testing solutions
Aluminum oxide catalyst, Glass wool, Alternative apparatus setup, Physical properties charts

KLB Secondary Chemistry Form 3, Pages 102-104

ORGANIC CHEMISTRY I

Chemical Properties of Alkenes - Addition Reactions

By the end of the lesson, the learner should be able to:
Explain addition reactions due to C=C double bond
Write equations for halogenation of alkenes
Describe hydrogenation and hydrohalogenation
Explain addition mechanism

In groups, learners are guided to:
Teacher exposition: Addition reactions definition and mechanism. Worked examples: Ethene + Cl₂, Br₂, HBr, H₂. Discussion: Markovnikov's rule for unsymmetrical addition. Practice: Various addition reaction equations.

Addition reaction charts, Mechanism diagrams, Chemical equation worksheets

KLB Secondary Chemistry Form 3, Pages 105-107

ORGANIC CHEMISTRY I

Oxidation Reactions of Alkenes and Polymerization
Tests for Alkenes and Uses

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

In groups, learners are guided to:
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
Test alkenes, Bromine water, Acidified KMnO₄, Plastic samples, Uses reference charts

KLB Secondary Chemistry Form 3, Pages 107-108

ORGANIC CHEMISTRY I

Introduction to Alkynes and Triple Bond

By the end of the lesson, the learner should be able to:
Define alkynes and triple bond structure
Write general formula for alkynes (CₙH₂ₙ₋₂)
Identify first members of alkyne series
Compare degree of unsaturation in hydrocarbons

In groups, learners are guided to:
Teacher exposition: Alkynes definition and C≡C triple bond. Table study: First 6 members of alkyne series with structures. Discussion: Degrees of unsaturation - alkanes vs alkenes vs alkynes. Model demonstration: Triple bond representation.

Alkyne series charts, Triple bond molecular models, Unsaturation comparison charts

KLB Secondary Chemistry Form 3, Pages 109-110

ORGANIC CHEMISTRY I

Nomenclature and Isomerism in Alkynes
Laboratory Preparation of Ethyne
Physical and Chemical Properties of 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
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

In groups, learners are guided to:
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.
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.

IUPAC naming rules for alkynes, Structural formula worksheets, Molecular model kits
Calcium carbide, Sand, Flat-bottomed flask, Dropping funnel, Gas collection apparatus, Testing solutions
Physical properties charts, Comparison tables, Combustion equation examples

KLB Secondary Chemistry Form 3, Pages 110-111
KLB Secondary Chemistry Form 3, Pages 111-112

ORGANIC CHEMISTRY I

Addition Reactions of Alkynes and Chemical Tests

By the end of the lesson, the learner should be able to:
Write equations for halogenation of alkynes
Describe hydrogenation and hydrohalogenation
Compare reaction rates: alkynes vs alkenes
Perform chemical tests for alkynes

In groups, learners are guided to:
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.

Addition reaction charts, Chemical equation worksheets, Test solutions, Stopwatch for rate comparison

KLB Secondary Chemistry Form 3, Pages 113-115

ORGANIC CHEMISTRY I

Uses of Alkynes and Industrial Applications

By the end of the lesson, the learner should be able to:
List industrial uses of alkynes
Explain oxy-acetylene welding applications
Describe use in synthetic fiber production
Evaluate importance as chemical starting materials

In groups, learners are guided to:
Discussion: Industrial applications of alkynes in adhesives, plastics, synthetic fibers. Teacher demonstration: Oxy-acetylene flame principles (or video). Q/A: Starting materials for chemical synthesis. Assignment: Research local industrial uses.

Industrial application charts, Welding equipment demonstration/video, Synthetic fiber samples

KLB Secondary Chemistry Form 3, Pages 115-116