CHEMISTRY · Pearson Edexcel IGCSE
CHEMISTRY/12
C (Core Theory)
Chemistry · June 2025 · Variant 2
Relative difficulty
Analysis source: Pearson Edexcel
Analysis aligned to the official syllabus and assessment design.
3.0 / 5
180
195 min
Energetics
Cohort performance
Session statistics from official examination reports
Total marks
180
Duration
195 min
Session difficulty
3.0 / 5
Key examiner messages
Top priorities from the principal examiner before you revise
The Summer 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars.
This series remained faithful to past trends, avoiding excessively convoluted experimental setups while testing critical core skills.
Well-prepared candidates had ample opportunity to secure high marks, while the papers successfully differentiated top-tier students through multi-step calculations and comparative structural explanations.
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.
Recall and Knowledge
Weight: 5100%Knowledge
Weight: 480%Application and P
Weight: 360%Experimental and
Weight: 240%Mathematical
Weight: 120%
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.
State features in sequence or list observable properties — do not explain causes unless asked.
Match the expected response style for “Give” questions.
Match the expected response style for “State” questions.
Name or point to the specific feature asked for — avoid extra explanation.
Time traps
Sections where candidates spent disproportionate time relative to marks
Min per mark: 1.1
Min per mark: 1.1
Min per mark: 1.1
Syllabus traceability
Topics linked to questions and mark weighting in this session
Energetics
19 marks this session
Chemical formulae, equations and calculations
17 marks this session
Crude oil
14 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
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
Energetics
19 marks this session
Practise in RevuiChemical formulae, equations and calculations
17 marks this session
Practise in RevuiCrude oil
14 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 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars.
- 2Message
This series remained faithful to past trends, avoiding excessively convoluted experimental setups while testing critical core skills.
- 3Message
Well-prepared candidates had ample opportunity to secure high marks, while the papers successfully differentiated top-tier students through multi-step calculations and comparative structural explanations.
Teacher briefing pack
One-page session summary for tutors and classroom review
June 2025 2025
Chemistry
The Summer 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars. This series remained faithful to past trends, avoiding
The Summer 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars.
This series remained faithful to past trends, avoiding excessively convoluted experimental setups while testing critical core skills.
Well-prepared candidates had ample opportunity to secure high marks, while the papers successfully differentiated top-tier students through multi-step calculations and comparative structural explanations.
- Total marks
- 180
- Duration
- 195 min
- Session difficulty
- 3.0 / 5
Session analysis
The Summer 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars. This series remained faithful to past trends, avoiding excessively convoluted experimental setups while testing critical core skills. Well-prepared candidates had ample opportunity to secure high marks, while the papers successfully differentiated top-tier students through multi-step calculations and comparative structural explanations.
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.
Short Answer
90·42·50%
Long Answer
54·12·30%
Calculations
32·8·18%
Multiple Choice
4·4·2%
Study ROI
Bigger bubbles recur more often; higher bubbles carry more marks, helping you rank revision priorities.
Difficulty trend
Compare difficulty across recent years.
Time vs marks
Compare marks with suggested time allocation to plan exam pacing.
Paper 1CR Section A
0.94 m/minPaper 2CR Section A
0.94 m/minPaper 2CR Section B
0.93 m/minTotal marks
117
Total time
125 min
Avg pace
0.94
Cumulative marks ladder
The line is your running mark total question by question; dashed lines are the estimated grade cut-offs. See which question the line crosses your target grade at, so you know how far you must answer cleanly and which questions decide a band.
Next-year prediction
Topics worth watching next year, with the reason shown directly below each bar.
Synthetic polymers
5%5%
Electrolysis
5%5%
Reversible reactions and equilibria
5%5%
Alkenes
4%4%
Overall Difficulty Verdict
The Summer 2025 series of the Pearson Edexcel International GCSE Chemistry (4CH1) exams (Papers 1CR and 2CR) provided a highly accessible yet rigorous assessment, receiving an overall difficulty rating of 3.0 out of 5 stars. This series remained faithful to past trends, avoiding excessively convoluted experimental setups while testing critical core skills. Well-prepared candidates had ample opportunity to secure high marks, while the papers successfully differentiated top-tier students through multi-step calculations and comparative structural explanations.
Exam tips
Paper format
- Duration
- 2h
- Total marks
- 110
- Weighting
- 61.1%
- Question types
- Multiple Choice / Drag-and-Drop Equivalents, Short recall and identification, Graphing & plotting skills, Calculations & quantitative formulas, Longer explanation / structured logic
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.