CHEMISTRY-XCH11 · Pearson Edexcel International AS Level
CHEMISTRY-XCH11/12
Paper 1
Chemistry · Winter 2026 · Variant 2
Relative difficulty
Analysis source: Pearson Edexcel
Analysis aligned to the official syllabus and assessment design.
3.6 / 5
210
260 min
Organic Chemistry: Alcohols, Halogenoalkanes, and Analytical Spectra
Cohort performance
Session statistics from official examination reports
Total marks
210
Duration
260 min
Session difficulty
3.6 / 5
Key examiner messages
Top priorities from the principal examiner before you revise
A significant portion of the marks in this series is allocated to Organic Chemistry: Alcohols, Halogenoalkanes and Spectra, which dominates across all three units.
Candidates who mastered reaction mechanisms (such as electrophilic addition with HBr and nucleophilic substitution with aqueous hydroxide) and spectral interpretation (identifying infrared stretches for C=O \text{C}=\text{O} C=O and N−H \text{N}-\text{H} N−H bonds) performed exceptionally well.
In contrast, marks were frequently dropped on Formulae, Equations and Amount of Substance due to a lack of precision in handling significant figures (which was explicitly assessed in the hydrated zinc sulfate crystal yield calculation) and algebraic rearrangements of the ideal gas equation pV=nRT pV = nRT pV=nRT where unit conversions for pressure and temperature were missed.
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.
Quantitative
Weight: 9100%Organic
Weight: 889%Reaction
Weight: 778%Practical Troubleshooting
Weight: 667%Inorganic
Weight: 444%Trends
Weight: 333%Extended Explanation
Weight: 222%
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
Level A
Approx. 80% of maximum mark
Level B
Approx. 70% of maximum mark
Level C
Approx. 60% of maximum mark
Level D
Approx. 50% of maximum mark
Level E
Approx. 40% of maximum mark
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
Show formula, substitution, and unit; method marks need visible working.
Give reasons and link mechanism to outcome; each point needs a because/so chain.
Match the expected response style for “Draw” questions.
Match the expected response style for “State” questions.
Name or point to the specific feature asked for — avoid extra explanation.
Apply knowledge to an unfamiliar context; concise, practical points score best.
State features in sequence or list observable properties — do not explain causes unless asked.
Time traps
Sections where candidates spent disproportionate time relative to marks
No data available in official reports
Syllabus traceability
Topics linked to questions and mark weighting in this session
Organic Chemistry: Alcohols, Halogenoalkanes and Spectra
52 marks this session
Formulae, Equations and Amount of Substance
26 marks this session
Redox Chemistry and Groups 1, 2 and 7
25 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
Organic Chemistry: Alcohols, Halogenoalkanes and Spectra
Formulae, Equations and Amount of Substance
Redox Chemistry and Groups 1, 2 and 7
Bonding and Structure
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
WCH11/01A: Structure, Bonding and Introduction to Organic Chemistry: WCH12/01A: Energetics, Group Chemistry, Halogenoalkanes and Alcohols: WCH13/01A: Practical Skills in Chemistry I:
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
Organic Chemistry: Alcohols, Halogenoalkanes and Spectra
52 marks this session
Practise in RevuiFormulae, Equations and Amount of Substance
26 marks this session
Practise in RevuiRedox Chemistry and Groups 1, 2 and 7
25 marks this session
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
A significant portion of the marks in this series is allocated to Organic Chemistry: Alcohols, Halogenoalkanes and Spectra, which dominates across all three units.
- 2Message
Candidates who mastered reaction mechanisms (such as electrophilic addition with HBr and nucleophilic substitution with aqueous hydroxide) and spectral interpretation (identifying infrared stretches for C=O \text{C}=\text{O} C=O and N−H \text{N}-\text{H} N−H bonds) performed exceptionally well.
- 3Message
In contrast, marks were frequently dropped on Formulae, Equations and Amount of Substance due to a lack of precision in handling significant figures (which was explicitly assessed in the hydrated zinc sulfate crystal yield calculation) and algebraic rearrangements of the ideal gas equation pV=nRT pV = nRT pV=nRT where unit conversions for pressure and temperature were missed.
Teacher briefing pack
One-page session summary for tutors and classroom review
Winter 2026 2026
Chemistry
A significant portion of the marks in this series is allocated to Organic Chemistry: Alcohols, Halogenoalkanes and Spectra, which dominates across all three units. Candidates who mastered reaction mechanisms (such as electrophilic addition with HBr and nucleophilic substitution w
A significant portion of the marks in this series is allocated to Organic Chemistry: Alcohols, Halogenoalkanes and Spectra, which dominates across all three units.
Candidates who mastered reaction mechanisms (such as electrophilic addition with HBr and nucleophilic substitution with aqueous hydroxide) and spectral interpretation (identifying infrared stretches for C=O \text{C}=\text{O} C=O and N−H \text{N}-\text{H} N−H bonds) performed exceptionally well.
In contrast, marks were frequently dropped on Formulae, Equations and Amount of Substance due to a lack of precision in handling significant figures (which was explicitly assessed in the hydrated zinc sulfate crystal yield calculation) and algebraic rearrangements of the ideal gas equation pV=nRT pV = nRT pV=nRT where unit conversions for pressure and temperature were missed.
- Total marks
- 210
- Duration
- 260 min
- Session difficulty
- 3.6 / 5
Session analysis
A significant portion of the marks in this series is allocated to Organic Chemistry: Alcohols, Halogenoalkanes and Spectra, which dominates across all three units. Candidates who mastered reaction mechanisms (such as electrophilic addition with HBr and nucleophilic substitution with aqueous hydroxide) and spectral interpretation (identifying infrared stretches for C=O \text{C}=\text{O} C=O and N−H \text{N}-\text{H} N−H bonds) performed exceptionally well. In contrast, marks were frequently dropped on Formulae, Equations and Amount of Substance due to a lack of precision in handling significant figures (which was explicitly assessed in the hydrated zinc sulfate crystal yield calculation) and algebraic rearrangements of the ideal gas equation pV=nRT pV = nRT pV=nRT where unit conversions for pressure and temperature were missed.
Updated Jun 12, 2026
Paper breakdown
WCH11/01A: Structure, Bonding and Introduction to Organic Chemistry: WCH12/01A: Energetics, Group Chemistry, Halogenoalkanes and Alcohols: WCH13/01A: Practical Skills in Chemistry I:
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.
76% 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
(Sections B & C)
115·45·55%
Multiple Choice
(Section A)
40·40·19%
Mathematical Calculations
40·12·19%
Practical Skills & Extended Writing
15·4·7%
Study ROI
Bigger bubbles recur more often; higher bubbles carry more marks, helping you rank revision priorities.
Next-year prediction
Topics worth watching next year, with the reason shown directly below each bar.
Group 2 Sulfates and Hydroxides Solubility Trends
85%85%
Redox Titrations (Thiosulfate/Iodine)
80%80%
Alkane Free Radical Substitution Halogenation Mechanisms
75%75%
Examiner notes & key calculations
- Incorrect State Symbols and Charges: In ionic equations, such as the reaction of zinc with sulfuric acid, candidates frequently wrote incorrect charges (e.g., H− \text{H}^- H−) or failed to include state symbols for spectator-deprived equations.
- Failing to Show Graphical Extrapolations: In WCH13, candidates were required to determine ΔT \Delta T ΔT using a cooling curve. Leaving out the drawn extrapolation lines to the mixing time of 3.5 minutes resulted in an automatic loss of construction marks, even if the final numerical value of ΔT \Delta T ΔT was correct.
- Vague Practical Explanations: In organic preparation questions, such as the reflux of hexan-1-ol, explaining the function of the Liebig condenser as simply "cooling the reaction" was insufficient; the mark scheme demanded explaining that vapours condense and return to the flask to ensure complete oxidation without loss of reactants.
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.