Cambridge IGCSE · Analysis & Prediction

2024 Cambridge IGCSE Chemistry (0620) Past Paper Analysis

This analysis covers the Cambridge IGCSE Chemistry (0620) May/June 2024 series, with a primary focus on the Extended route (Papers 22, 42, and 62). The papers offer a well-structured assessment of the syllabus, featuring core conceptual areas such as organic chemistry, stoichiometry, reactivity of metals, and chemical reactions. Key highlights include challenging stoichiometry equations, a classic bond energy calculation in the Haber process context, and an elegant experimental design problem on extracting bismuth from bismite.

Updated: 13 Jun 2026

Analysis Sample paper

Difficulty 3.5/5

Total marks

160

Duration

180 mins

Most tested

Reactivity and Extraction of Metals

Paper breakdown

Paper 22 (Extended Multiple Choice): 40 marks · 45 minsPaper 42 (Extended Theory): 80 marks · 75 minsPaper 62 (Alternative to Practical): 40 marks · 60 mins

Top chapters

Reactivity series · 16 marksAcid–base titrations · 15 marksFormulae (Stoichiometry) · 12 marksIdentification of ions and gases · 11 marksAlcohols · 10 marks

May/June 2024 Exam Analysis: IGCSE Chemistry (0620)

The May/June 2024 sitting of the IGCSE Chemistry (0620) examination provided a comprehensive and rigorous assessment of candidates' knowledge across both Core and Extended tiers. Our focus on the Extended route (Papers 22, 42, and 62) reveals a paperset that rewards precise chemical vocabulary, thorough practical familiarity, and neat algebraic processing. The overall difficulty aligns well with historical averages, sitting at a balanced 3.5 out of 5, though some novel contexts in Paper 42 and Paper 62 tested top-end candidates' ability to apply theory to unfamiliar situations.

Where the Marks are Won or Lost

In Paper 42, high-value marks were heavily concentrated in the stoichiometry, organic synthesis, and chemical equilibrium sections. The stoichiometry questions demanded complex equation balancing (such as the reduction of \(\text{Fe}_3\text{O}_4\) with \(\text{HCl}\)) and multi-step mass-to-volume gas calculations. Candidates who demonstrated methodical working secured full marks here. In Paper 62, the experimental analysis of an aluminium chloride titration with sodium hydroxide represented a significant chunk of marks. Precision in reading burettes to one decimal place and understanding the role of the thymolphthalein indicator were crucial. The final 6-mark planning question on extracting bismuth from bismite was a differentiator; marks were awarded for recognizing the insolubility of bismuth(III) oxide and proposing a step-by-step separation before reduction.

Examiner Pitfalls & Critical Traps

The examiner reports highlight several recurring areas where even high-performing students threw away marks:

Bond Energy Bookkeeping: In the Haber process calculation, many students calculated the reactant bond-breaking energy correctly but failed to account for all six \(\text{N–H}\) bonds in the products (from \(2\text{NH}_3\)).
Vague Comparisons in Displacement: When describing the displacement reactions, candidates frequently stated that 'the metal is reactive' or 'it is more reactive' without explicitly comparing it to the other metal in the pair.
Molten vs. Aqueous State: In the ionic conductivity question, writing that magnesium sulfide conducts electricity because 'ions can move' was insufficient without specifying that it must be in the molten or aqueous state.
Displayed Formulas: Drawing organic structures with pentavalent carbons or neglecting to show the bond between oxygen and hydrogen (\(\text{O–H}\)) in alcohols remain classic pitfalls.

Strategic Preparation Tips

To master upcoming sessions, students must adopt a dual-focus strategy. First, elevate your chemical formula game. Do not just memorise common binary salts; practice writing reactions for mixed-oxidation oxides like \(\text{Fe}_3\text{O}_4\) and complex anions. Second, internalise the qualitative analysis notes. Knowing the exact observations for testing transition metal cations and halide anions is non-negotiable—they represent 'free' marks that build confidence early in the papers.

Future Predictions & Outlooks

Looking ahead to the next series, we predict a strong pivot back towards detailed organic polymerisation mechanisms, specifically comparing condensation polymers (like polyesters) with addition polymerisation. Additionally, complex electrolysis systems—specifically the industrial electrolysis of brine or aluminum extraction—are highly likely to feature as major structured questions, as they were relatively quiet in this series. Ensure you can confidently state the ionic reactions taking place at both the anode and cathode.

Charts

Marks by chapter

See where the marks were concentrated so revision time goes to the highest-value topics.

Question type mix

Compare the mark share of each paper section and question type.

Multiple Choice40 marks · 40 questions
Structured Questions80 marks · 28 questions
Alternative to Practical40 marks · 14 questions

Mark accessibility

Estimate which marks were basic, mid-level, or high-difficulty.

81%within easy or medium reach

easy: 60 marksmedium: 70 markshard: 30 marks

Difficulty trend

Compare difficulty across recent years.

Command word frequency

Spot common command words so answers match the expected response style.

Skill weighting

Shows the skill mix this paper tested most heavily.

Study ROI

Bigger bubbles recur more often; higher bubbles carry more marks, helping you rank revision priorities.

Reactivity series

16 marks · Difficulty 3 · recurrence 100%

Acid–base titrations

15 marks · Difficulty 3.2 · recurrence 95%

Identification of ions and gases

11 marks · Difficulty 2 · recurrence 100%

Ions and ionic bonds

9 marks · Difficulty 2.2 · recurrence 90%

Reversible reactions and equilibrium

11 marks · Difficulty 3.5 · recurrence 90%

Time vs marks

Compare marks with suggested time allocation to plan exam pacing.

marksmins

Next-year prediction

Topics worth watching next year, with the reason shown directly below each bar.

Stoichiometry (The Mole and Avogadro)95%

A core mathematical topic that is guaranteed to appear with multi-step mole calculations, particularly limiting reactants or percentage yield.

Polymers (Organic Chemistry)90%

Only a brief monomer question was present in Paper 2/4. Synthetic addition and condensation polymerisation (nylons/polyesters) are highly likely to feature heavily in the next theory series.

Electrolysis (Electrochemistry)85%

Only basic molten/solution concepts were tested. A detailed calculation or gas volume ratio analysis in dilute aqueous systems is due next.

Topic-year heatmap

Compare topic weight by year to spot recurring and returning areas.

Jun 2023 (V1)

Jun 2023 (V2)

Jun 2023 (V3)

Nov 2023 (V1)

Nov 2023 (V2)

Nov 2023 (V3)

Jun 2024 (V1)

Jun 2024 (V2)

Separation and purification

Atomic structure and the Periodic Table

Isotopes

Relative masses of atoms and molecules

Ions and ionic bonds

Simple molecules and covalent bonds

Rate of reaction

The mole and the Avogadro constant

Physical and chemical changes

Electrolysis

Examiner insights

Official report

Common pitfalls

In the bond energy calculation, candidates often failed to account for the six N–H bonds in two molecules of ammonia (2NH3), using three or four instead.
Stating that 'magnesium is more reactive' without specifying the comparison to iron when describing displacement results.
Omitting state symbols when completing reaction equations (e.g., in the nitrogen pentoxide decomposition question).

Misconceptions

Believing that catalysts alter the equilibrium yield of a reaction rather than just accelerating both forward and reverse rates.
Thinking that a volumetric pipette can be used to measure variable volumes in a titration experiment.
Confusing physical changes (like dissolving NaCl in water) with chemical reactions due to temperature/energy transfers.

Where marks are lost

Failing to specify 'molten' when describing how magnesium sulfide conducts electricity (simple mention of ions without state/movement was penalised).
Incomplete displayed formulas in organic chemistry, such as leaving off a hydrogen atom or drawing five-bonded carbons.
Forgetting to filter out the soluble impurities first in the planning question for extracting bismuth, leading to contaminated metal.

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