THE MOLE

Relative Mass - Introduction and Experimental Investigation

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

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.

Different sized nails ( 5-15cm), Beam balance, Fruits of different masses, Reference charts

KLB Secondary Chemistry Form 3, Pages 25-27

THE MOLE

Avogadro's Constant and the Mole Concept

By the end of the lesson, the learner should be able to:
Define Avogadro's constant and its value
Explain the concept of a mole as a counting unit
Relate molar mass to relative atomic mass
Calculate number of atoms in given masses of elements

Experiment: Determine number of nails with mass equal to relative mass in grams. Teacher exposition: Introduce Avogadro's constant (6.023 × 10²³). Discussion: Mole as counting unit like dozen. Worked examples: Calculate moles from mass and vice versa.

Beam balance, Various sized nails, Scientific calculators, Avogadro's constant charts

KLB Secondary Chemistry Form 3, Pages 27-30

THE MOLE

Interconversion of Mass and Moles for Elements

By the end of the lesson, the learner should be able to:
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

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.

Scientific calculators, Periodic table, Worked example charts, Formula triangles

KLB Secondary Chemistry Form 3, Pages 30-32

THE MOLE

Molecules and Moles - Diatomic Elements

By the end of the lesson, the learner should be able to:
Distinguish between atoms and molecules
Define relative molecular mass
Calculate moles of molecules from given mass
Determine number of atoms in molecular compounds

Discussion: Elements existing as molecules (O₂, H₂, N₂, Cl₂). Teacher exposition: Difference between atomic and molecular mass. Worked examples: Calculate moles of molecular elements. Problem solving: Number of atoms in molecular compounds.

Molecular models, Charts showing diatomic elements, Scientific calculators

KLB Secondary Chemistry Form 3, Pages 29-30

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

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

KLB Secondary Chemistry Form 3, Pages 35-37

THE MOLE

Empirical Formula - Percentage Composition Method
Molecular Formula - Determination from Empirical Formula

By the end of the lesson, the learner should be able to:
Calculate empirical formula from percentage composition
Convert percentages to moles
Determine simplest whole number ratios
Apply method to various compounds
Define molecular formula
Relate molecular formula to empirical formula
Calculate molecular formula using molecular mass
Apply the relationship (empirical formula)ₙ = molecular formula

Worked examples: Calculate empirical formula from percentage data. Method: percentage → mass → moles → ratio. Practice problems: Various compounds with different compositions. Discussion: When to multiply ratios to get whole numbers.
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, Percentage composition charts, Worked example displays
Scientific calculators, Molecular mass charts, Worked example displays

KLB Secondary Chemistry Form 3, Pages 37-38
KLB Secondary Chemistry Form 3, Pages 38-40

THE MOLE

Molecular Formula - Combustion Analysis

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

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.

Scientific calculators, Combustion analysis charts, Molecular models of hydrocarbons

KLB Secondary Chemistry Form 3, Pages 40-41

THE MOLE

Concentration and Molarity of Solutions

By the end of the lesson, the learner should be able to:
Define concentration and molarity of solutions
Calculate molarity from mass and volume data
Convert between different concentration units
Apply molarity calculations to various solutions

Teacher exposition: Definition of molarity (moles/dm³). Worked examples: Calculate molarity from mass of solute and volume. Convert between g/dm³ and mol/dm³. Practice problems: Various salt solutions and their molarities.

Scientific calculators, Molarity charts, Various salt samples for demonstration

KLB Secondary Chemistry Form 3, Pages 41-43

THE MOLE

Concentration and Molarity of Solutions

By the end of the lesson, the learner should be able to:
Define concentration and molarity of solutions
Calculate molarity from mass and volume data
Convert between different concentration units
Apply molarity calculations to various solutions

Teacher exposition: Definition of molarity (moles/dm³). Worked examples: Calculate molarity from mass of solute and volume. Convert between g/dm³ and mol/dm³. Practice problems: Various salt solutions and their molarities.

Scientific calculators, Molarity charts, Various salt samples for demonstration

KLB Secondary Chemistry Form 3, Pages 41-43

THE MOLE

Preparation of Molar Solutions
Dilution of Solutions

By the end of the lesson, the learner should be able to:
Describe procedure for preparing molar solutions
Use volumetric flasks correctly
Calculate masses needed for specific molarities
Prepare standard solutions accurately
Define dilution process
Apply dilution formula M₁V₁ = M₂V₂
Calculate concentrations after dilution
Prepare dilute solutions from concentrated ones

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.
Experiment: Dilute 25cm³ of 2M HCl to different final volumes (250cm³ and 500cm³). Calculate resulting concentrations. Worked examples using dilution formula. Safety precautions when diluting acids.

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 43-46
KLB Secondary Chemistry Form 3, Pages 46-50

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

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

KLB Secondary Chemistry Form 3, Pages 53-56

THE MOLE

Stoichiometry - Gas Evolution Reactions

By the end of the lesson, the learner should be able to:
Determine stoichiometry of gas-producing reactions
Collect and measure gas volumes
Calculate mole ratios involving gases
Write equations for acid-carbonate reactions

Experiment: HCl + Na₂CO₃ reaction. Collect CO₂ gas in plastic bag. Measure gas mass and calculate moles. Determine mole ratios of reactants and products. Write balanced equation.

Conical flask, Thistle funnel, Plastic bags, Rubber bands, Sodium carbonate, HCl solution

KLB Secondary Chemistry Form 3, Pages 56-58

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

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

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.

Burettes, Pipettes, 0.1M NaOH, 0.1M HCl, Phenolphthalein indicator, Conical flasks

KLB Secondary Chemistry Form 3, Pages 59-62

THE MOLE

Titration - Diprotic Acids

By the end of the lesson, the learner should be able to:
Investigate titrations involving diprotic acids
Determine basicity of acids from titration data
Compare volumes needed for mono- and diprotic acids
Write equations for diprotic acid reactions

Experiment: Titrate 25cm³ of 0.1M NaOH with 0.1M H₂SO₄. Compare volume used with previous HCl titration. Calculate mole ratios. Explain concept of basicity. Introduce dibasic and tribasic acids.

Burettes, Pipettes, 0.1M H₂SO₄, 0.1M NaOH, Phenolphthalein, Basicity reference chart

KLB Secondary Chemistry Form 3, Pages 62-65

THE MOLE

Standardization of Solutions
Back Titration Method

By the end of the lesson, the learner should be able to:
Define standardization process
Standardize HCl using Na₂CO₃ as primary standard
Calculate accurate concentrations from titration data
Understand importance of primary standards
Understand principle of back titration
Apply back titration to determine composition
Calculate concentrations using back titration data
Determine atomic masses from back titration

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.
Experiment: Determine atomic mass of divalent metal in MCO₃. Add excess HCl to carbonate, then titrate excess with NaOH. Calculate moles of acid that reacted with carbonate. Determine metal's atomic mass.

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 65-67
KLB Secondary Chemistry Form 3, Pages 67-70

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

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

KLB Secondary Chemistry Form 3, Pages 70-72

THE MOLE

Water of Crystallization Determination
Atomicity and Molar Gas Volume

By the end of the lesson, the learner should be able to:
Determine water of crystallization in hydrated salts
Use redox titration to find formula of hydrated salt
Calculate value of 'n' in crystallization formulas
Apply analytical data to determine complete formulas
Define atomicity of gaseous elements
Classify gases as monoatomic, diatomic, or triatomic
Determine molar gas volume experimentally
Calculate gas densities and molar masses

Experiment: Determine 'n' in FeSO₄(NH₄)₂SO₄·nH₂O. Dissolve known mass in acid, titrate with standardized KMnO₄. Calculate moles of iron(II), hence complete formula. Compare theoretical and experimental values.
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.

Hydrated iron(II) salt, Standardized KMnO₄, Dilute H₂SO₄, Analytical balance
Gas syringes (50cm³), Various gases, Analytical balance, Gas supply apparatus

KLB Secondary Chemistry Form 3, Pages 72-73
KLB Secondary Chemistry Form 3, Pages 73-75

THE MOLE

Combining Volumes of Gases - Experimental Investigation

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

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.

Gas syringes, Dry NH₃ generator, Dry HCl generator, Glass connecting tubes, Clips

KLB Secondary Chemistry Form 3, Pages 75-77

THE MOLE

Gas Laws and Chemical Equations

By the end of the lesson, the learner should be able to:
Apply Avogadro's law to chemical reactions
Use volume ratios to determine chemical equations
Calculate product volumes from reactant volumes
Solve problems involving gas stoichiometry

Worked examples: Use Gay-Lussac's law to determine equations. Calculate volumes of products from given reactant volumes. Apply Avogadro's law to find number of molecules. Practice: Complex gas stoichiometry problems.

Scientific calculators, Gas law charts, Volume ratio examples

KLB Secondary Chemistry Form 3, Pages 77-79

CHLORINE AND ITS COMPOUNDS

Introduction and Preparation of Chlorine

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

KLB Secondary Chemistry Form 4, Pages 195-196

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.
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 6.2 - 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.
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.

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
KLB Secondary Chemistry Form 4, Pages 199-201

CHLORINE AND ITS COMPOUNDS

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 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

KLB Secondary Chemistry Form 4, Pages 201

CHLORINE AND ITS COMPOUNDS

Reaction of Chlorine with Alkali Solutions
Oxidising Properties - Displacement Reactions

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

KLB Secondary Chemistry Form 4, Pages 202-203

CHLORINE AND ITS COMPOUNDS

Test for Chloride Ions
Uses of Chlorine and its Compounds

By the end of the lesson, the learner should be able to:
Carry out confirmatory tests for chloride ions. Distinguish between different chloride tests. Practice qualitative analysis techniques. Write equations for chloride ion tests.
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.

Practical work: Experiment 6.9 - Testing sodium chloride with concentrated H2SO4, testing with lead(II) nitrate solution. Recording observations in Table 6. Tests: White fumes with H2SO4 + ammonia test, white precipitate with Pb(NO3)2 that dissolves on warming. Writing equations: NaCl + H2SO4 → NaHSO4 + HCl, Pb²⁺ + 2Cl⁻ → PbCl
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.

Sodium chloride, Concentrated H2SO4, Lead(II) nitrate solution, Aqueous ammonia, Glass rod, Test tubes, Bunsen burner
Charts showing industrial uses, Samples of bleaching agents, PVC materials, Photographs of water treatment plants, Industrial application diagrams

KLB Secondary Chemistry Form 4, Pages 204-205
KLB Secondary Chemistry Form 4, Pages 205-207

CHLORINE AND ITS COMPOUNDS

Hydrogen Chloride - Laboratory Preparation

By the end of the lesson, the learner should be able to:
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.

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.

Rock salt (NaCl), Concentrated H2SO4, Gas collection apparatus, Ammonia solution, Litmus papers, Water trough, Gas jars

KLB Secondary Chemistry Form 4, Pages 207-208

CHLORINE AND ITS COMPOUNDS

Chemical Properties of Hydrogen Chloride

By the end of the lesson, the learner should be able to:
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.

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.

Distilled water, Filter funnel, Metals (Zn, Fe, Mg, Cu), NaOH solution, Carbonates, Lead nitrate, Methylbenzene, Indicators

KLB Secondary Chemistry Form 4, Pages 208-211

CHLORINE AND ITS COMPOUNDS

Large-scale Manufacture 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

KLB Secondary Chemistry Form 4, Pages 211-212

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.
List the industrial uses of hydrochloric acid. Explain applications in metal treatment. Describe use in water treatment and manufacturing. Relate acid properties to industrial applications.

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.
Discussion: Applications - rust removal and descaling, galvanizing preparation, electroplating preparation, water treatment (chlorination), sewage treatment. Manufacturing uses: dyes, drugs, photographic materials (AgCl), pH control in industries. Q/A: How acid properties make HCl suitable for these uses. Case studies: Metal cleaning processes, water purification systems.

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
KLB Secondary Chemistry Form 4, Pages 212-213

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