NITROGEN AND ITS COMPOUNDS

Introduction to Nitrogen - Properties and Occurrence
Isolation of Nitrogen from Air - Industrial and Laboratory Methods

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

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
Aspirator, KOH solution, Copper turnings, Heating apparatus, Fractional distillation flow chart

KLB Secondary Chemistry Form 3, Pages 119

NITROGEN AND ITS COMPOUNDS

Laboratory Preparation of Nitrogen Gas
Properties and Uses of Nitrogen Gas
Nitrogen(I) Oxide - Preparation and Properties

By the end of the lesson, the learner should be able to:
Prepare nitrogen gas from ammonium compounds
Use sodium nitrite and ammonium chloride method
Test physical and chemical properties of nitrogen
Write equations for nitrogen preparation
Describe physical properties of nitrogen
Explain chemical inertness of nitrogen
Describe reactions at high temperatures
List industrial uses of nitrogen

Experiment: Mix sodium nitrite (7g) and ammonium chloride ( 5g) with water. Heat gently and collect gas over water. Tests: Color, smell, burning splint, litmus paper, lime water, burning Mg and S. Safety precautions during heating.
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.

Sodium nitrite, Ammonium chloride, Round-bottomed flask, Gas collection apparatus, Test reagents, Deflagrating spoon
Property summary charts, Uses of nitrogen displays, Industrial application diagrams
Ammonium nitrate, Test tubes, Gas collection apparatus, Copper turnings, Sulfur, Glowing splints

KLB Secondary Chemistry Form 3, Pages 121-123

NITROGEN AND ITS COMPOUNDS

Nitrogen(II) 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

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

KLB Secondary Chemistry Form 3, Pages 125-127

NITROGEN AND ITS COMPOUNDS

Nitrogen(IV) Oxide - Preparation and Properties
Comparison of Nitrogen Oxides and Environmental Effects

By the end of the lesson, the learner should be able to:
Prepare nitrogen(IV) oxide from copper and concentrated nitric acid
Prepare from thermal decomposition of nitrates
Test properties including equilibrium with N₂O₄
Describe reactions and uses

Experiment: Add concentrated HNO₃ to copper turnings. Collect red-brown gas by downward delivery. Alternative: Heat lead(II) nitrate with cooling U-tube. Tests: Solubility, effect on litmus, burning elements, cooling/heating effects.

Copper turnings, Concentrated nitric acid, Lead(II) nitrate, Gas collection apparatus, U-tube with ice, Testing materials
Comparison charts, Environmental impact diagrams, Vehicle emission illustrations

KLB Secondary Chemistry Form 3, Pages 127-131

NITROGEN AND ITS COMPOUNDS

Laboratory Preparation of Ammonia

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

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.

Calcium hydroxide, Ammonium chloride, Round-bottomed flask, Calcium oxide, HCl solution, Glass rod, Litmus paper

KLB Secondary Chemistry Form 3, Pages 131-134

NITROGEN AND ITS COMPOUNDS

Preparation of Aqueous Ammonia and Solubility
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:
Prepare aqueous ammonia solution
Demonstrate high solubility using fountain experiment
Explain alkaline properties of aqueous ammonia
Write equations for ammonia in water
Test reactions of aqueous ammonia with various metal ions
Observe precipitate formation and dissolution
Explain complex ion formation
Use reactions for metal ion identification

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.
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⁺.

Ammonia generation apparatus, Funnel, Universal indicator, Fountain apparatus, pH meter/paper
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 134-136
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

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
Nitrogenous Fertilizers - Types and Calculations

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

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
Various fertilizer formulas, Scientific calculators, Laboratory preparation materials, Environmental impact data

KLB Secondary Chemistry Form 3, Pages 141-144

NITROGEN AND ITS COMPOUNDS

Laboratory Preparation of Nitric(V) Acid

By the end of the lesson, the learner should be able to:
Prepare nitric acid from nitrate and concentrated sulfuric acid
Set up all-glass apparatus safely
Explain brown fumes and yellow color
Purify nitric acid by air bubbling

Experiment: Heat mixture of KNO₃ and concentrated H₂SO₄ in all-glass apparatus. Collect yellow nitric acid. Explain brown fumes (NO₂) and yellow color. Bubble air through to remove dissolved NO₂. Safety: Gentle heating, fume cupboard.

Potassium nitrate, Concentrated sulfuric acid, All-glass apparatus, Condenser, Retort stand, Safety equipment

KLB Secondary Chemistry Form 3, Pages 144-145

NITROGEN AND ITS COMPOUNDS

Industrial Manufacture of Nitric(V) Acid
Reactions of Dilute Nitric(V) Acid with Metals

By the end of the lesson, the learner should be able to:
Describe catalytic oxidation process
Explain raw materials and conditions
Draw flow diagram of industrial process
Calculate theoretical yields and efficiency

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.

Industrial process flow charts, Catalyst samples, Process condition charts, Efficiency calculation sheets
Various metals (Mg, Zn, Cu), Dilute nitric acid, Test tubes, Gas testing apparatus, Burning splints

KLB Secondary Chemistry Form 3, Pages 145-147

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

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

Reactions of Concentrated Nitric(V) Acid - Oxidizing Properties
Uses of Nitric(V) Acid and Introduction to Nitrates
Action of Heat on Nitrates - Decomposition Patterns

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
Test thermal decomposition of different nitrates
Classify decomposition patterns based on metal reactivity
Identify products formed on heating
Write equations for decomposition reactions

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.
Experiment: Heat KNO₃, NaNO₃, Zn(NO₃)₂, Cu(NO₃)₂, NH₄NO₃ separately. Test gases with glowing splint. Observe residues. Classification: Group I nitrates → nitrite + O₂; Group II → oxide + NO₂ + O₂; NH₄NO₃ → N₂O + H₂O.

Concentrated nitric acid, Iron(II) sulfate, Sulfur powder, Copper turnings, Test tubes, Fume cupboard access
Industrial use charts, Nitrate salt samples, Preparation method diagrams, Safety data sheets
Various nitrate salts, Test tubes, Bunsen burner, Gas collection apparatus, Glowing splints, Observation recording sheets

KLB Secondary Chemistry Form 3, Pages 150-151
KLB Secondary Chemistry Form 3, Pages 151-153

NITROGEN AND ITS COMPOUNDS

Test for Nitrates - Brown Ring Test
Environmental Pollution by Nitrogen Compounds

By the end of the lesson, the learner should be able to:
Perform brown ring test for nitrates
Explain mechanism of complex formation
Use alternative copper test method
Apply tests to unknown samples

Experiments: (a) Brown ring test - add FeSO₄ solution to nitrate, then carefully add concentrated H₂SO₄. Observe brown ring formation. (b) Alternative test - warm nitrate with H₂SO₄ and copper turnings. Observe brown fumes. Test unknown samples.

Sodium nitrate, Fresh FeSO₄ solution, Concentrated H₂SO₄, Copper turnings, Test tubes, Unknown nitrate samples
Environmental pollution charts, Acid rain effect photos, Vehicle emission diagrams, Control measure illustrations

KLB Secondary Chemistry Form 3, Pages 153-154

NITROGEN AND ITS COMPOUNDS

Pollution Control and Environmental Solutions

By the end of the lesson, the learner should be able to:
Analyze methods to reduce nitrogen pollution
Design pollution control strategies
Evaluate effectiveness of current measures
Propose new solutions for environmental protection

Discussion and analysis: Catalytic converters in vehicles, sewage treatment, lime addition to soils/lakes, proper fertilizer application, industrial gas recycling. Group activity: Design pollution control strategy for local area. Evaluation of current measures.

Case studies, Pollution control technology information, Group activity worksheets, Local environmental data

KLB Secondary Chemistry Form 3, Pages 154-157

NITROGEN AND ITS COMPOUNDS

Comprehensive Problem Solving - Nitrogen Chemistry
Laboratory Practical Assessment - Nitrogen Compounds

By the end of the lesson, the learner should be able to:
Solve complex problems involving nitrogen compounds
Apply knowledge to industrial processes
Calculate yields and percentages in reactions
Analyze experimental data and results

Problem-solving session: Mixed calculations involving nitrogen preparation, ammonia synthesis, nitric acid concentration, fertilizer analysis. Industrial application problems. Data analysis from experiments. Integration of all nitrogen chemistry concepts.

Scientific calculators, Comprehensive problem sets, Industrial data sheets, Experimental result tables
Unknown nitrogen compounds, All laboratory chemicals and apparatus used in chapter, Safety equipment, Assessment rubrics

KLB Secondary Chemistry Form 3, Pages 119-157

NITROGEN AND ITS COMPOUNDS
NITROGEN AND ITS COMPOUNDS
CHLORINE AND ITS COMPOUNDS

Industrial Applications and Economic Importance
Chapter Review and Integration
Introduction and Preparation of Chlorine

By the end of the lesson, the learner should be able to:
Evaluate economic importance of nitrogen industry
Analyze industrial production costs and benefits
Compare different manufacturing processes
Assess impact on agricultural productivity
Synthesize all nitrogen chemistry concepts
Compare preparation methods for nitrogen compounds
Relate structure to properties and reactivity
Connect laboratory and industrial processes

Case study analysis: Haber process economics, fertilizer industry impact, nitric acid production costs. Agricultural benefits: Crop yield improvements, food security. Economic calculations: Production costs, profit margins, environmental costs. Global nitrogen cycle importance.
Comprehensive review: Concept mapping of all nitrogen compounds and their relationships. Comparison tables: Preparation methods, properties, uses. Flow chart: Nitrogen cycle in industry and environment. Integration exercises connecting all topics.

Economic data sheets, Industry case studies, Agricultural statistics, Cost-benefit analysis templates
Concept mapping materials, Comparison charts, Flow diagram templates, Integration worksheets
Manganese(IV) oxide, Concentrated HCl, Gas collection apparatus, Water, Concentrated H2SO4, Blue litmus paper, Gas jars

KLB Secondary Chemistry Form 3, Pages 119-157

CHLORINE AND ITS COMPOUNDS

Physical Properties of Chlorine
Chemical Properties of Chlorine - Reaction with Water
Chemical Properties of Chlorine - Reaction with Metals

By the end of the lesson, the learner should be able to:
Investigate the physical properties of chlorine gas. Explain the method of collection used for chlorine. Test the solubility of chlorine in water. State the density and color of chlorine gas.

Practical work: Experiment 6.2 - Testing chlorine gas preserved from previous experiment. Recording observations in Table 6. Testing: Color, smell (caution - no direct smelling), density, solubility in water. Demonstration: Inverting gas jar in water trough. Discussion: Why collected by downward delivery.

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
Magnesium ribbon, Iron wire, Chlorine gas, Deflagrating spoon, Combustion tube, Anhydrous CaCl2, Gas jars

KLB Secondary Chemistry Form 4, Pages 196-197

CHLORINE AND ITS COMPOUNDS

Chemical Properties of Chlorine - Reaction with Non-metals
Oxidising Properties of Chlorine
Reaction of Chlorine with Alkali Solutions

By the end of the lesson, the learner should be able to:
Investigate reactions of chlorine with non-metals. Demonstrate reaction with phosphorus and hydrogen. Write equations for non-metal chloride formation. Explain the vigorous nature of these reactions.

Practical work: Experiment 6.5 - Warming red phosphorus and lowering into chlorine. Demonstration: Burning hydrogen jet in chlorine. Observations: White fumes of phosphorus chlorides, hydrogen chloride formation. Writing equations: P4 + 6Cl2 → 4PCl3, H2 + Cl2 → 2HCl. Discussion: Formation of covalent chlorides.

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
Sodium hydroxide solutions (dilute cold, concentrated hot), Chlorine gas, Beakers, Bunsen burner, Thermometer

KLB Secondary Chemistry Form 4, Pages 201

CHLORINE AND ITS COMPOUNDS

Oxidising Properties - Displacement Reactions
Test for Chloride Ions

By the end of the lesson, the learner should be able to:
Investigate displacement reactions of chlorine with halides. Test reactions with bromides and iodides. Write ionic equations for displacement reactions. Explain the order of reactivity of halogens.

Practical work: Experiment 6.8 - Bubbling chlorine through potassium bromide and potassium iodide solutions. Observations: Colorless to orange (Br2), colorless to brown (I2). Writing ionic equations: Cl2 + 2Br⁻ → 2Cl⁻ + Br2, Cl2 + 2I⁻ → 2Cl⁻ + I Discussion: Displacement as evidence of relative reactivity.

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 203-204

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.
Prepare aqueous hydrogen chloride (hydrochloric acid). Investigate acid properties of HCl solution. Test reactions with metals, bases, and carbonates. Compare HCl in water vs organic solvents.

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 6.11 - Preparation of aqueous HCl using apparatus in Figure 6. Testing with metals (Zn, Fe, Mg, Cu), NaOH, carbonates, lead nitrate. Recording observations in Table 6.7. Testing HCl in methylbenzene - no acid properties. Discussion: Ionization in water vs molecular existence in organic solvents. Writing equations for acid reactions.

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 208-211

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