Inorganic Chemistry

Periodicity - Introduction to halogens

By the end of the lesson, the learner should be able to:
- Identify elements in the halogen family
- Describe electron configuration of halogens
- Relate halogen reactivity to their use in water treatment and disinfectants

In groups, learners are guided to:
- Determine chemical family of chlorine and fluorine
- Write electron configurations
- List other halogens

Why are halogens called "salt formers"?

- Front Row Chemistry Grade 10 pg. 114
- Periodic table
- Digital devices

- Oral questions - Written exercises - Observation

Inorganic Chemistry

Periodicity - Laboratory preparation of chlorine gas
Periodicity - Trends in physical properties of halogens (atomic radii, melting and boiling points)
Periodicity - Appearance, physical state and solubility of halogens

By the end of the lesson, the learner should be able to:
- Prepare chlorine gas in the laboratory
- Describe properties of chlorine gas
- Relate chlorine properties to its use in bleach and water purification
- Describe appearance and physical states of halogens
- Investigate solubility in water and organic solvents
- Relate iodine's colour to its use as antiseptic in wound treatment

In groups, learners are guided to:
- Prepare chlorine gas from HCl and MnO₂
- Collect chlorine gas
- Observe properties of chlorine
- Observe appearance of chlorine, bromine and iodine
- Test solubility in water
- Compare solubility of halogens

How is chlorine gas prepared and collected safely?
Why do halogens have different colours and physical states?

- Front Row Chemistry Grade 10 pg. 115
- MnO₂, conc. HCl
- Round bottomed flask
- Gas jars
- Front Row Chemistry Grade 10 pg. 117
- Data tables
- Periodic table
- Front Row Chemistry Grade 10 pg. 118
- Bromine, iodine samples
- Distilled water
- Test tubes

- Practical assessment - Written exercises - Observation

Inorganic Chemistry

Periodicity - Electrical conductivity of halogens

By the end of the lesson, the learner should be able to:
- Investigate electrical conductivity of halogens
- Explain why halogens do not conduct electricity
- Contrast halogen non-conductivity with metal conductivity in wiring

In groups, learners are guided to:
- Test electrical conductivity of iodine crystals
- Discuss results in terms of structure
- Compare with ionic and metallic substances

Why don't halogens conduct electricity?

- Front Row Chemistry Grade 10 pg. 120
- Iodine crystals
- Circuit with bulb
- Beaker

- Practical assessment - Written exercises - Observation

Inorganic Chemistry

Periodicity - Electron affinity and ion formation of halogens

By the end of the lesson, the learner should be able to:
- Define electron affinity
- Explain trends in electron affinity down Group VII
- Relate electron affinity to halogen reactivity in forming salts

In groups, learners are guided to:
- Understand how halogen atoms form ions
- Discuss electron affinity values
- Explain trend down the group

Why does electron affinity decrease down Group VII?

- Front Row Chemistry Grade 10 pg. 121
- Data tables
- Digital devices

- Written exercises - Oral questions - Individual assessment

Inorganic Chemistry

Periodicity - Reaction of halogens with metals

By the end of the lesson, the learner should be able to:
- Investigate reactions of halogens with metals
- Write balanced equations for the reactions
- Relate iron chloride formation to industrial rust prevention

In groups, learners are guided to:
- React chlorine with iron and zinc
- Observe products formed
- Write balanced equations

What happens when halogens react with metals?

- Front Row Chemistry Grade 10 pg. 122
- Iron filings
- Chlorine gas
- Combustion tube

- Practical assessment - Written exercises - Observation

Inorganic Chemistry

Periodicity - Reaction of chlorine with water
Periodicity - Displacement reactions of halogens
Periodicity - Applications of halogens

By the end of the lesson, the learner should be able to:
- Investigate reaction of chlorine with water
- Describe bleaching action of chlorine water
- Relate chlorine water to swimming pool disinfection
- Identify uses of halogens
- Relate properties to applications
- Connect fluoride in toothpaste to dental health protection

In groups, learners are guided to:
- Prepare chlorine water
- Test with litmus paper
- Investigate decomposition in sunlight
- Search for information on uses of halogens
- Discuss applications of F, Cl, Br and I
- Present findings to class

How does chlorine react with water and why is it used as a bleach?
How are halogens used in water treatment, medicine and industry?

- Front Row Chemistry Grade 10 pg. 124
- Chlorine gas
- Distilled water
- Litmus paper
- Front Row Chemistry Grade 10 pg. 125
- Chlorine, bromine water
- KBr, KI solutions
- Test tubes
- Front Row Chemistry Grade 10 pg. 127
- Digital devices
- Product samples

- Practical assessment - Written exercises - Observation
- Oral questions - Written exercises - Group presentations

Inorganic Chemistry

Periodicity - Introduction to noble gases

By the end of the lesson, the learner should be able to:
- Identify noble gases and their electron configurations
- Explain why noble gases are chemically inert
- Relate noble gas stability to their use in light bulbs and balloons

In groups, learners are guided to:
- Determine electronic configuration of noble gases
- Discuss stability of full electron shells
- List noble gas elements

Why are noble gases unreactive?

- Front Row Chemistry Grade 10 pg. 128
- Periodic table
- Digital devices

- Oral questions - Written exercises - Observation

Inorganic Chemistry

Periodicity - Trends in physical properties of noble gases

By the end of the lesson, the learner should be able to:
- Describe trends in physical properties of noble gases
- Explain trends in ionisation energy
- Relate noble gas properties to neon signs and helium balloons

In groups, learners are guided to:
- Review atomic structure of noble gases
- Study trends in atomic radii and ionisation energy
- Discuss reactivity based on electron configuration

Why do noble gases have very high ionisation energies?

- Front Row Chemistry Grade 10 pg. 129
- Data tables
- Periodic table

- Written exercises - Oral questions - Observation

Inorganic Chemistry

Periodicity - Applications of noble gases

By the end of the lesson, the learner should be able to:
- Identify uses of noble gases
- Relate properties to applications
- Connect argon's inertness to its use in welding and light bulbs

In groups, learners are guided to:
- Search for information on uses of noble gases
- Discuss applications of He, Ne and Ar
- Present findings to class

How are noble gases used despite being unreactive?

- Front Row Chemistry Grade 10 pg. 131
- Digital devices
- Pictures of applications

- Oral questions - Written exercises - Group presentations

Inorganic Chemistry

Periodicity - Introduction to Period 3 elements
Periodicity - Trends in atomic radii across Period 3
Periodicity - Trends in ionisation energy across Period 3

By the end of the lesson, the learner should be able to:
- Identify Period 3 elements and their properties
- Classify elements as metals, metalloids or non-metals
- Relate Period 3 elements to common materials like aluminium foil and silicon chips
- Describe trends in ionisation energy across Period 3
- Explain factors affecting ionisation energy
- Relate ionisation energy to metallic character of sodium vs non-metallic chlorine

In groups, learners are guided to:
- List Period 3 elements from Na to Ar
- Discuss bonding and structure of each element
- Classify elements by type
- Study ionisation energy data for Period 3
- Discuss trend and anomalies
- Explain using atomic structure

What elements are found in Period 3 and how do their properties vary?
Why does ionisation energy generally increase across Period 3?

- Front Row Chemistry Grade 10 pg. 131
- Periodic table
- Element samples
- Front Row Chemistry Grade 10 pg. 132
- Data tables
- Graph paper
- Front Row Chemistry Grade 10 pg. 133
- Data tables
- Digital devices

- Oral questions - Written exercises - Observation
- Written exercises - Oral questions - Individual assessment

Inorganic Chemistry

Periodicity - Trends in melting and boiling points across Period 3

By the end of the lesson, the learner should be able to:
- Describe trends in melting and boiling points across Period 3
- Explain trends using structure and bonding
- Relate silicon's high melting point to its use in computer chips

In groups, learners are guided to:
- Study data on melting and boiling points
- Relate trends to bonding and structure
- Explain anomalies

Why does silicon have the highest melting point in Period 3?

- Front Row Chemistry Grade 10 pg. 134
- Data tables
- Charts

- Written exercises - Oral questions - Observation

Inorganic Chemistry

Periodicity - Electron affinity and electronegativity across Period 3

By the end of the lesson, the learner should be able to:
- Define electron affinity and electronegativity
- Describe trends across Period 3
- Relate electronegativity to bond polarity in water molecules

In groups, learners are guided to:
- Discuss electron affinity trends
- Study electronegativity values across Period 3
- Explain factors affecting these properties

Why does electronegativity increase across Period 3?

- Front Row Chemistry Grade 10 pg. 135
- Data tables
- Digital devices

- Written exercises - Oral questions - Individual assessment

Inorganic Chemistry

Periodicity - Reaction of Period 3 elements with oxygen (Na, Mg, Al)

By the end of the lesson, the learner should be able to:
- Investigate reactions of Na, Mg and Al with oxygen
- Write balanced equations for the reactions
- Relate magnesium oxide formation to its use in antacids and refractory materials

In groups, learners are guided to:
- Burn sodium, magnesium and aluminium in air
- Observe products formed
- Write word and chemical equations

What products form when Period 3 metals burn in oxygen?

- Front Row Chemistry Grade 10 pg. 136
- Na, Mg, Al samples
- Bunsen burner
- Deflagrating spoon

- Practical assessment - Written exercises - Observation

Inorganic Chemistry

Periodicity - Reaction of Period 3 elements with oxygen (Si, P, S)
Periodicity - Reaction of Period 3 elements with chlorine (Na, Mg, Al)
Periodicity - Reaction of Period 3 elements with chlorine (Si, P)

By the end of the lesson, the learner should be able to:
- Describe reactions of Si, P and S with oxygen
- Write balanced equations for the reactions
- Relate sulphur dioxide formation to air pollution and acid rain
- Describe reactions of Si and P with chlorine
- Write balanced equations for the reactions
- Relate silicon tetrachloride to semiconductor manufacturing

In groups, learners are guided to:
- Discuss reactions of silicon and phosphorus with oxygen
- Burn sulphur in oxygen
- Write balanced equations
- Discuss reactions of silicon and phosphorus with chlorine
- Write balanced equations
- Compare metal and non-metal chlorides

What products form when Period 3 non-metals burn in oxygen?
What are the products when Period 3 non-metals react with chlorine?

- Front Row Chemistry Grade 10 pg. 136
- Sulphur powder
- Gas jar of oxygen
- Deflagrating spoon
- Front Row Chemistry Grade 10 pg. 137
- Na, Mg samples
- Chlorine gas
- Front Row Chemistry Grade 10 pg. 138
- Reference materials
- Digital devices

- Practical assessment - Written exercises - Observation
- Written exercises - Oral questions - Observation

Inorganic Chemistry

Periodicity - Reaction of Period 3 elements with water (Na, Mg)

By the end of the lesson, the learner should be able to:
- Investigate reactions of sodium and magnesium with water
- Compare reactivity of the two metals
- Relate sodium hydroxide formation to soap making

In groups, learners are guided to:
- React sodium and magnesium with cold water
- React magnesium with steam
- Write balanced equations

Why does sodium react more vigorously with water than magnesium?

- Front Row Chemistry Grade 10 pg. 140
- Sodium, magnesium
- Trough with water
- Phenolphthalein

- Practical assessment - Written exercises - Observation

Inorganic Chemistry

Periodicity - Reaction of Period 3 elements with dilute acids

By the end of the lesson, the learner should be able to:
- Investigate reactions of Period 3 metals with dilute acids
- Write balanced equations for the reactions
- Relate hydrogen gas production to laboratory gas collection techniques

In groups, learners are guided to:
- React magnesium and aluminium with dilute HCl and H₂SO₄
- Test gas produced
- Write balanced equations

What products form when Period 3 metals react with dilute acids?

- Front Row Chemistry Grade 10 pg. 139
- Mg ribbon
- Dilute HCl, H₂SO₄
- Test tubes

- Practical assessment - Written exercises - Observation

Inorganic Chemistry
Physical Chemistry
Physical Chemistry

Periodicity - Comparison of trends across Period 3 and down groups
Acids and Bases - Dissociation of acids in water
Acids and Bases - Dissociation of bases in water

By the end of the lesson, the learner should be able to:
- Compare periodic trends across periods and down groups
- Summarise factors affecting periodic properties
- Apply periodic trends to predict element behaviour in new materials

In groups, learners are guided to:
- Compare trends across Period 3 with trends down groups
- Create summary tables of periodic trends
- Discuss patterns and exceptions

How do trends across a period differ from trends down a group?

- Front Row Chemistry Grade 10 pg. 141
- Summary charts
- Periodic table
- Front Row Chemistry Learner's Book pg. 143
- Distilled water
- Hydrochloric acid
- Blue and red litmus papers
- Beakers
- Stirring rod
- Sodium hydroxide
- Measuring cylinder

- Written exercises - Oral questions - Individual assessment

Physical Chemistry

Acids and Bases - Reaction of acids with metals
Acids and Bases - Reaction of acids with metals (continued)
Acids and Bases - Reaction of acids with carbonates and hydrogen carbonates
Acids and Bases - Reaction of acids with hydrogen carbonates

By the end of the lesson, the learner should be able to:
- Describe the reaction between acids and metals
- Test for hydrogen gas produced during the reaction
- Connect the corrosion of metal roofs by acid rain to acid-metal reactions
- Describe reactions between acids and carbonates
- Test for carbon (IV) oxide gas produced
- Connect the effervescence of antacid tablets in water to carbonate-acid reactions

In groups, learners are guided to:
- Carry out experiments on reactions between dilute acids and metals (zinc, magnesium, iron)
- Test for hydrogen gas using a burning splint
- Write balanced chemical equations for the reactions
- Carry out experiments on reactions of acids with sodium carbonate and calcium carbonate
- Pass gas produced through lime water
- Write balanced chemical equations for the reactions

What gas is produced when metals react with acids?
How can you confirm the presence of carbon (IV) oxide gas?

- Front Row Chemistry Learner's Book pg. 144
- Zinc granules
- Magnesium ribbon
- Iron filings
- Dilute HCl and H₂SO₄
- Test tubes
- Wooden splints
- Front Row Chemistry Learner's Book pg. 146
- Aluminium foil
- Copper turnings
- Dilute HCl
- Dilute H₂SO₄
- Test tubes
- Front Row Chemistry Learner's Book pg. 147
- Sodium carbonate
- Calcium carbonate
- Dilute HCl
- Lime water
- Delivery tubes
- Test tubes
- Sodium hydrogen carbonate
- Test tubes
- Delivery tubes

- Practical assessment - Written equations - Oral questions

Physical Chemistry

Acids and Bases - Reaction of acids with metal hydroxides
Acids and Bases - Reaction of acids with metal oxides
Acids and Bases - Amphoteric oxides and hydroxides

By the end of the lesson, the learner should be able to:
- Describe neutralisation reactions between acids and metal hydroxides
- Determine the endpoint of a neutralisation reaction using indicators
- Connect the use of antacids to neutralise stomach acid to acid-base reactions

In groups, learners are guided to:
- Carry out experiments on reactions of acids with sodium hydroxide using phenolphthalein indicator
- Observe colour changes at the endpoint
- Write balanced chemical equations

What is the role of phenolphthalein in neutralisation reactions?

- Front Row Chemistry Learner's Book pg. 148
- Sodium hydroxide
- Dilute HCl
- Phenolphthalein indicator
- Droppers
- Beakers
- Stirring rod
- Front Row Chemistry Learner's Book pg. 150
- Zinc oxide
- Copper (II) oxide
- Universal indicator
- Filter funnel and paper
- Front Row Chemistry Learner's Book pg. 151
- Test tubes
- Spatula

- Practical assessment - Written equations - Oral questions

Physical Chemistry

Acids and Bases - Universal indicator and pH scale

By the end of the lesson, the learner should be able to:
- Explain the pH scale and its range
- Determine the pH of solutions using universal indicator
- Relate the pH of common household substances to their acidic or basic nature

In groups, learners are guided to:
- Carry out experiments to determine pH of various solutions using universal indicator
- Compare colours with pH chart
- Record observations in a table

How does the pH scale help us classify substances?

- Front Row Chemistry Learner's Book pg. 152
- Universal indicator
- pH chart
- Sulphuric (VI) acid
- Ethanoic acid
- Sodium hydroxide
- Test tubes

- Practical assessment - Written tests - Oral questions

Physical Chemistry

Acids and Bases - Strong and weak acids

By the end of the lesson, the learner should be able to:
- Distinguish between strong and weak acids based on dissociation
- Compare pH values of strong and weak acids
- Connect the mild taste of vinegar compared to the corrosive nature of car battery acid to acid strength

In groups, learners are guided to:
- Compare pH values of sulphuric (VI) acid and ethanoic acid
- Discuss complete versus partial dissociation
- Write dissociation equations for strong and weak acids

Why do strong acids have lower pH values than weak acids?

- Front Row Chemistry Learner's Book pg. 153
- Sulphuric (VI) acid
- Ethanoic acid
- Universal indicator
- pH chart
- Test tubes

- Observation - Oral questions - Written assignments

Physical Chemistry

Acids and Bases - Strong and weak bases
Acids and Bases - Electrical conductivity of acids and bases

By the end of the lesson, the learner should be able to:
- Distinguish between strong and weak bases based on dissociation
- Compare pH values of strong and weak bases
- Relate the effectiveness of different cleaning agents to base strength
- Investigate electrical conductivity of strong and weak acids and bases
- Relate conductivity to concentration of ions in solution
- Connect the use of dilute acids in batteries to their electrical conductivity

In groups, learners are guided to:
- Compare pH values of sodium hydroxide and ammonia solution
- Discuss ionisation of strong and weak bases
- Record observations and conclusions
- Set up electrical conductivity experiments
- Compare ammeter readings for different solutions
- Discuss relationship between ion concentration and conductivity

Why is sodium hydroxide a better drain cleaner than ammonia?
Why do strong acids conduct electricity better than weak acids?

- Front Row Chemistry Learner's Book pg. 154
- Sodium hydroxide
- Ammonia solution
- Universal indicator
- pH chart
- Test tubes
- Front Row Chemistry Learner's Book pg. 154
- Electrodes
- Ammeter
- Beakers
- Dilute HCl
- Ethanoic acid
- NaOH solution
- Ammonia solution

- Practical assessment - Written tests - Oral questions
- Practical assessment - Observation - Written assignments

Physical Chemistry

Acids and Bases - Applications of acids and bases
Introduction to Salts - Definition and formation of salts
Introduction to Salts - Normal salts

By the end of the lesson, the learner should be able to:
- Outline applications of acids and bases in various industries
- Search for information on uses of acids and bases
- Identify the role of acids and bases in household cleaning, food preservation, and agriculture

In groups, learners are guided to:
- Search for information using digital or print media on applications of acids and bases
- Discuss uses in agriculture, food industry, medicine, and manufacturing
- Test pH of common household substances

How are acids and bases used in our daily lives?

- Front Row Chemistry Learner's Book pg. 157
- Lemon juice
- Baking soda
- Soap solution
- Vinegar
- Universal indicator
- Digital devices
- Front Row Chemistry Learner's Book pg. 160
- Dilute HCl
- Magnesium ribbon
- Universal indicator paper
- pH chart
- Test tubes
- Burning splint
- Front Row Chemistry Learner's Book pg. 162
- Sodium chloride
- Calcium nitrate
- Sodium sulphate
- Distilled water
- Red and blue litmus papers
- Boiling tubes

- Group presentations - Written assignments - Oral questions

Physical Chemistry

Introduction to Salts - Acid salts
Introduction to Salts - Basic salts

By the end of the lesson, the learner should be able to:
- Define acid salts
- Identify examples of acid salts
- Connect the use of sodium hydrogen carbonate (baking soda) in baking to its acidic properties

In groups, learners are guided to:
- Carry out experiments to identify acid salts using litmus papers
- Test pH of solutions of acid salts
- Discuss partial replacement of hydrogen ions

Why do acid salt solutions turn blue litmus red?

- Front Row Chemistry Learner's Book pg. 164
- Sodium hydrogen sulphate
- Sodium hydrogen carbonate
- Distilled water
- Red and blue litmus papers
- Boiling tubes
- Front Row Chemistry Learner's Book pg. 165
- Basic magnesium chloride
- Basic copper carbonate

- Observation - Written assignments - Oral questions

Physical Chemistry

Introduction to Salts - Double salts
Introduction to Salts - Solubility rules for salts
Introduction to Salts - Preparation of soluble salts by action of acid on metal

By the end of the lesson, the learner should be able to:
- Define double salts
- Identify examples of double salts
- Relate potassium aluminium sulphate (alum) to its use in water purification

In groups, learners are guided to:
- Carry out experiments to identify double salts
- Discuss the presence of two different cations or anions
- Write formulae of double salts

Why do double salts have a neutral pH in solution?

- Front Row Chemistry Learner's Book pg. 166
- Potassium aluminium sulphate
- Ammonium iron (II) sulphate
- Distilled water
- Red and blue litmus papers
- Boiling tubes
- Front Row Chemistry Learner's Book pg. 167
- Lead chloride
- Ammonium nitrate
- Sodium sulphate
- Zinc carbonate
- Test tubes
- Heat source
- Zinc powder
- Dilute HCl
- Beakers
- Filter funnel and paper
- Evaporating dish
- Water bath

- Observation - Written assignments - Oral questions

Physical Chemistry

Introduction to Salts - Preparation of soluble salts by action of acid on insoluble base
Introduction to Salts - Preparation of soluble salts by neutralisation (acid and alkali)
Introduction to Salts - Preparation of soluble salts by reaction of acid with carbonates

By the end of the lesson, the learner should be able to:
- Prepare soluble salts by reacting acids with insoluble bases
- Write balanced chemical equations for the preparation
- Relate the preparation of copper (II) nitrate to its use as a fungicide in agriculture
- Prepare soluble salts by reacting acids with carbonates
- Write balanced chemical equations for the reactions
- Relate the reaction of limestone (calcium carbonate) with acid to the weathering of buildings and monuments

In groups, learners are guided to:
- Carry out experiments to prepare copper (II) nitrate from copper (II) oxide and dilute nitric acid
- Filter, evaporate, and crystallise the salt
- Discuss why excess base is added
- Carry out experiments to prepare zinc sulphate from zinc carbonate and dilute sulphuric (VI) acid
- Test for carbon (IV) oxide produced
- Filter, evaporate, and crystallise

Why is the metal oxide added in excess during salt preparation?
What gas is produced when carbonates react with acids?

- Front Row Chemistry Learner's Book pg. 169
- Copper (II) oxide
- Dilute nitric (V) acid
- Beakers
- Filter funnel and paper
- Evaporating dish
- Heat source
- Front Row Chemistry Learner's Book pg. 171
- Sodium hydroxide
- Dilute HCl
- Phenolphthalein indicator
- Burette
- Conical flask
- Evaporating dish
- Front Row Chemistry Learner's Book pg. 173
- Zinc carbonate
- Dilute sulphuric (VI) acid
- Lime water
- Beakers
- Filter funnel and paper
- Evaporating dish

- Practical assessment - Written tests - Oral questions

Physical Chemistry

Introduction to Salts - Preparation of insoluble salts by precipitation

By the end of the lesson, the learner should be able to:
- Prepare insoluble salts by precipitation
- Write balanced chemical and ionic equations for precipitation reactions
- Connect the formation of limescale in kettles to the precipitation of insoluble calcium compounds

In groups, learners are guided to:
- Carry out experiments to prepare lead (II) sulphate by precipitation
- Filter and wash the precipitate
- Write ionic equations for the reaction

How are insoluble salts prepared in the laboratory?

- Front Row Chemistry Learner's Book pg. 174
- Lead (II) nitrate solution
- Sodium sulphate solution
- Beakers
- Filter funnel and paper
- Distilled water

- Practical assessment - Written equations - Observation

Physical Chemistry

Introduction to Salts - Preparation of salts by direct combination

By the end of the lesson, the learner should be able to:
- Prepare salts by direct combination of elements
- Write balanced chemical equations for direct synthesis reactions
- Relate the tarnishing of silver jewellery to the direct combination of silver with sulphur

In groups, learners are guided to:
- Carry out experiments to prepare iron (II) sulphide by direct synthesis
- Heat iron filings and sulphur powder
- Observe and record changes

How can salts be prepared without using acids?

- Front Row Chemistry Learner's Book pg. 176
- Iron filings
- Sulphur powder
- Crucible
- Heat source
- Tongs
- Spatula

- Practical assessment - Observation - Oral questions

Physical Chemistry

Introduction to Salts - Deliquescence, hygroscopy, and efflorescence
Introduction to Salts - Applications of deliquescent and hygroscopic salts

By the end of the lesson, the learner should be able to:
- Define deliquescence, hygroscopy, and efflorescence
- Investigate the behaviour of salts when exposed to air
- Relate the caking of table salt in humid weather to hygroscopy

In groups, learners are guided to:
- Carry out experiments to investigate behaviour of salts in air
- Expose sodium chloride, calcium chloride, and sodium carbonate to air
- Record observations over time

Why do some salts absorb moisture from the atmosphere?

- Front Row Chemistry Learner's Book pg. 177
- Sodium chloride
- Calcium chloride
- Sodium carbonate
- Watch glasses
- Labels
- Front Row Chemistry Learner's Book pg. 178
- Anhydrous calcium chloride
- Anhydrous copper (II) sulphate
- Cobalt (II) chloride paper
- Digital devices

- Observation - Written assignments - Oral questions

Physical Chemistry

Introduction to Salts - Uses of salts in agriculture and food industry
Introduction to Salts - Environmental effects and mitigation measures

By the end of the lesson, the learner should be able to:
- Outline uses of salts in agriculture and food industry
- Search for information on applications of salts
- Identify the role of fertilisers in improving crop yields and food preservation using salt
- Explain the effects of excessive use of inorganic fertilisers on the environment
- Discuss mitigation measures for environmental challenges
- Connect water pollution and algal blooms in lakes to eutrophication caused by fertiliser runoff

In groups, learners are guided to:
- Discuss uses of salts in agriculture (fertilisers)
- Discuss uses in food industry (preservatives, flavouring)
- Search for information using digital or print media
- Search for information on effects of inorganic fertilisers on the environment
- Discuss eutrophication, soil degradation, and groundwater contamination
- Brainstorm mitigation measures for sustainable agriculture

How do farmers use salts to improve crop production?
How can we reduce the negative effects of fertilisers on the environment?

- Front Row Chemistry Learner's Book pg. 179
- Samples of fertilisers
- Table salt
- Baking soda
- Digital devices
- Reference books
- Front Row Chemistry Learner's Book pg. 181
- Digital devices
- Reference books
- Charts showing eutrophication

- Group presentations - Written assignments - Oral questions