CHEMISTRY · Pearson Edexcel IGCSE
CHEMISTRY/22
C (Advanced Applications)
Chemistry · 2023 · Variant 2
Relative difficulty
Analysis source: Pearson Edexcel
Analysis aligned to the official syllabus and assessment design.
3.5 / 5
180
195 min
Stoichiometric calculations, chemical formulas, and empirical/molecular formula determinations.
Cohort performance
Session statistics from official examination reports
Total marks
180
Duration
195 min
Session difficulty
3.5 / 5
Key examiner messages
Top priorities from the principal examiner before you revise
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus.
With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the entire grade boundary spectrum.
While candidates demonstrated exceptional proficiency in procedural mathematical questions, they faced substantial difficulties when tasked with precise scientific explanations, experimental design, and the application of practical laboratory knowledge.
Question difficulty map
How candidates performed on each question in this series
No data available in official reports
Assessment objectives
Skill and AO weighting from official examiner commentary
Skill weighting
Shows the skill mix this paper tested most heavily.
AO1 - Knowledge w
Weight: 4100%Knowledge aAO2 -
Weight: 375%ApplicationAO3 -
Weight: 250%Experimental
Weight: 125%
Method marks watchlist
Where working, steps, or method marks were commonly lost
No data available in official reports
Recurring mistakes across years
Themes examiners flag in multiple recent sessions for this subject
No data available in official reports
Question choice intelligence
Mean scores and popularity for optional questions (HKDSE electives)
No data available in official reports
Level exemplars
What candidate scripts at each grade level looked like
No data available in official reports
Grade & admission context
How marks relate to grade thresholds and entry standards
Report type
Examiner report — national grade boundaries and question-level commentary
Deep insights
What top candidates did
Techniques and approaches examiners rewarded in this series
No data available in official reports
Command word playbook
How to match each command word to the expected response style
Give reasons and link mechanism to outcome; each point needs a because/so chain.
Show formula, substitution, and unit; method marks need visible working.
Match the expected response style for “State” questions.
State features in sequence or list observable properties — do not explain causes unless asked.
Match the expected response style for “Determine” questions.
Match the expected response style for “Complete” questions.
Apply knowledge to an unfamiliar context; concise, practical points score best.
Time traps
Sections where candidates spent disproportionate time relative to marks
Min per mark: 1.2
Min per mark: 1.2
Min per mark: 1
Syllabus traceability
Topics linked to questions and mark weighting in this session
Chemical formulae, equations and calculations
24 marks this session
Energetics
19 marks this session
Reactivity series
12 marks this session
MCQ trap analytics
Commonly chosen wrong options from examiner commentary
No data available in official reports
Topic heatmap across years
Mark concentration by topic and exam year for this subject
Mark intensity
Chemical formulae, equations and calculations
Energetics
Crude oil
Elements, compounds and mixtures
Alcohols
Reactivity series
Rates of reaction
Alkenes
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
Paper 1CR:
Paper 2CR:
Marks you can still earn
Where valid approaches outside the mark scheme may still gain credit
No data available in official reports
Practise what examiners flagged
Target weak topics from this report inside the Revui app
Chemical formulae, equations and calculations
24 marks this session
Practise in RevuiEnergetics
19 marks this session
Practise in RevuiReactivity series
12 marks this session
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus.
- 2Message
With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the entire grade boundary spectrum.
- 3Message
While candidates demonstrated exceptional proficiency in procedural mathematical questions, they faced substantial difficulties when tasked with precise scientific explanations, experimental design, and the application of practical laboratory knowledge.
Teacher briefing pack
One-page session summary for tutors and classroom review
2023 2023
Chemistry
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus. With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus.
With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the entire grade boundary spectrum.
While candidates demonstrated exceptional proficiency in procedural mathematical questions, they faced substantial difficulties when tasked with precise scientific explanations, experimental design, and the application of practical laboratory knowledge.
- Total marks
- 180
- Duration
- 195 min
- Session difficulty
- 3.5 / 5
Session analysis
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus. With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the entire grade boundary spectrum. While candidates demonstrated exceptional proficiency in procedural mathematical questions, they faced substantial difficulties when tasked with precise scientific explanations, experimental design, and the application of practical laboratory knowledge.
Updated Jun 13, 2026
Paper breakdown
Paper 1CR:
Paper 2CR:
Top chapters
Exam structure insights
Marks by chapter
See where the marks were concentrated so revision time goes to the highest-value topics.
Mark accessibility
Estimate which marks were basic, mid-level, or high-difficulty.
78% within easy or medium reach
Command word frequency
Spot common command words so answers match the expected response style.
Question type mix
Compare the mark share of each paper section and question type.
Structured/Short Answer
115·48·64%
Calculations
38·15·21%
Practical/Experimental Design
15·3·8%
Multiple Choice
12·12·7%
Study ROI
Bigger bubbles recur more often; higher bubbles carry more marks, helping you rank revision priorities.
Time vs marks
Compare marks with suggested time allocation to plan exam pacing.
Paper 1CR (Recall &…
0.86 m/minPaper 1CR (Experime…
0.96 m/minPaper 2CR (Recall &…
0.87 m/minTotal marks
100
Total time
110 min
Avg pace
0.91
Next-year prediction
Topics worth watching next year, with the reason shown directly below each bar.
Carboxylic Acids & Condensation Polymerisation
85%85%
Gas preparation methods (e.g., preparation of carbon dioxide/oxygen)
78%78%
Executive Difficulty Verdict
The Summer 2023 Pearson Edexcel International GCSE Chemistry papers (1CR and 2CR) presented a highly balanced, fair, yet rigorous assessment of the syllabus. With a combined total of 180 marks across 195 minutes of examination, the assessment successfully discriminated across the entire grade boundary spectrum. While candidates demonstrated exceptional proficiency in procedural mathematical questions, they faced substantial difficulties when tasked with precise scientific explanations, experimental design, and the application of practical laboratory knowledge.
Exam tips
Paper format
- Duration
- 1h 15min
- Total marks
- 70
- Weighting
- 38.9%
- Question types
- Multiple Choice, Recall tables & diagrams, Multi-step physical calculation (bond energies, yields), Experimental design and evaluation
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.