Cambridge Cambridge IGCSE Chemistry

Cambridge Cambridge IGCSE Chemistry Learning Path

Detailed syllabus unit mapping, custom lesson objectives, required laboratory practical guides, and assessment MCQ checklists.

Explore chemical classifications, stoichiometry mole ratios, electrochemistry, redox, acid-base neutralizations, and organic structures.

Lesson Plans & Objectives

Relative Formula Mass (Mr)50 min

Calculate Ar and Mr of compounds.
Solve molecular formula mass weights.

Mole Calculations50 min

State Avogadro's number relation.
Calculate mass from moles: m = n · M.

Suggested Practical Activities

Determining the empirical formula of Magnesium Oxide by heating ribbon in crucible

Revision Notes

One mole of any substance contains 6.022 × 10²³ particles (Avogadro's Constant).
Mole calculation: moles (n) = mass (g) / molar mass (g/mol).

CAIE Worked Examples & Mark Scheme Breakdown

Example 1: Calculating Relative Formula Mass (Mr)CAIE Step-by-Step

Calculate the relative formula mass (Mr) of hydrated copper(II) sulfate, CuSO₄·5H₂O (Ar: Cu=64, S=32, O=16, H=1).

Step 1: Calculate Mr of anhydrous CuSO₄64 + 32 + (4 × 16) = 64 + 32 + 64 = 160

Step 2: Calculate mass of 5 water molecules 5H₂O5 × (2 + 16) = 5 × 18 = 90

Step 3: Sum totals160 + 90 = 250

Final CAIE Answer:Mr = 250

Example 2: Mass of Reactant Needed in Reacting MassesCAIE Step-by-Step

Calculate the mass of Carbon Dioxide produced when 50 g of Calcium Carbonate (CaCO₃, Mr=100) decomposes completely: CaCO₃ → CaO + CO₂ (Mr of CO₂=44).

Step 1: Calculate moles of CaCO₃n = 50 g / 100 g/mol = 0.50 moles

Step 2: Determine mole ratio1 mole CaCO₃ yields 1 mole CO₂ → 0.50 moles CO₂

Step 3: Calculate mass of CO₂mass = 0.50 mol × 44 g/mol = 22 g

Final CAIE Answer:22 g of CO₂

Example 3: Percentage Yield CalculationCAIE Step-by-Step

In an experiment, 12.5 g of copper product was obtained, but theoretical calculation predicted 16.0 g. Calculate percentage yield.

Step 1: State formulaPercentage Yield = (Actual Yield / Theoretical Yield) × 100%

Step 2: Substitute values(12.5 / 16.0) × 100% = 0.78125 × 100%

Step 3: Round answer78.1%

Final CAIE Answer:78.1%

Example 4: Molar Volume of Gas at RTPCAIE Step-by-Step

Calculate the volume occupied by 0.30 moles of Nitrogen gas (N₂) at room temperature and pressure (Molar gas volume = 24 dm³/mol).

Step 1: State molar volume formulaVolume = moles × 24 dm³/mol

Step 2: Calculate in dm³V = 0.30 × 24 = 7.2 dm³

Final CAIE Answer:7.2 dm³ (7200 cm³)

Example 5: Empirical Formula from Percentage CompositionCAIE Step-by-Step

A compound contains 40.0% Carbon, 6.7% Hydrogen, and 53.3% Oxygen by mass. Determine its empirical formula (Ar: C=12, H=1, O=16).

Step 1: Divide percentage by ArC: 40/12 = 3.33; H: 6.7/1 = 6.7; O: 53.3/16 = 3.33

Step 2: Divide by smallest mole value (3.33)C: 3.33/3.33 = 1; H: 6.7/3.33 = 2; O: 3.33/3.33 = 1

Step 3: Write empirical formulaCH₂O

Final CAIE Answer:CH₂O

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Cambridge Cambridge IGCSE Chemistry Learning Path

Stoichiometry & Mole Concept

Lesson Plans & Objectives

Suggested Practical Activities

Revision Notes

CAIE Worked Examples & Mark Scheme Breakdown

Cambridge Cambridge IGCSE Chemistry Learning Path

Stoichiometry & Mole Concept

Lesson Plans & Objectives

Suggested Practical Activities

Revision Notes

CAIE Worked Examples & Mark Scheme Breakdown