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CHEMISTRY · HKDSE

CHEMISTRY/21

(Elective Part)

Chemistry · 2024 · Variant 1

Relative difficulty

Demanding · 3.8/5

Analysis source: Hong Kong Examinations and Assessment Authority (HKEAA)

Analysis aligned to the official syllabus and assessment design.

Relative difficulty

3.8 / 5

Total marks

160

Duration

210 min

Most tested topic

Analytical and Industrial Chemistry Electives

Cohort performance

Session statistics from official examination reports

Total marks

160

Duration

210 min

Session difficulty

3.8 / 5

Level 5**

~95% of max

Level 5*

~91% of max

Level 5

~85% of max

Key examiner messages

Top priorities from the principal examiner before you revise

1

The 2024 Chemistry paper maintained a robust standard of assessment, showcasing a moderate-to-high difficulty level (3.8/5). Paper 1B (Conventional) demanded strong conceptual mastery, especially in topics like chemical cells and organic synthesis. Paper 2 (Electives) tested stud

2

The 2024 HKDSE Chemistry exam presented a highly balanced structure.

3

It tested core chemical concepts alongside challenging application questions, particularly in organic mechanisms, Arrhenius kinetics, and complex electrochemical cells.

4

Well-prepared students who excelled in precision of terminology and quantitative calculations achieved excellent results.

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

Conceptual Understanding7
Quantitative5
Experimental4
Logic3
Scientific Communication2

Skill weighting

Shows the skill mix this paper tested most heavily.

Conceptual UnderstandingConceptualUnderstandingQuantitativeQuantitativeExperimentalExperimentalLogicLogicScientific CommunicationScientificCommunication
SkillWeightShare
  • Conceptual Understanding

    Weight: 7100%
  • Quantitative

    Weight: 571%
  • Experimental

    Weight: 457%
  • Logic

    Weight: 343%
  • Scientific Communication

    Weight: 229%

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

Reporting source

HKEAA Subject Examination Report — comments on candidates’ performance with marking schemes

Level 5**

Outstanding — competitive JUPAS programmes (medicine, law, top faculties)

Level 5*

Excellent — strong JUPAS profile for selective programmes

Level 5

Good — meets most university entrance requirements

Level 4

Satisfactory — foundation programmes or less selective routes

Level 3

Pass threshold for many sub-degree and vocational pathways

Admission context

Levels feed JUPAS and non-JUPAS university applications; 5** and 5* are most selective

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

ExplainFrequency: 18

Give reasons and link mechanism to outcome; each point needs a because/so chain.

CalculateFrequency: 10

Show formula, substitution, and unit; method marks need visible working.

DrawFrequency: 6

Match the expected response style for “Draw” questions.

SuggestFrequency: 8

Apply knowledge to an unfamiliar context; concise, practical points score best.

DescribeFrequency: 5

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

Paper 2 (Elective S60m / 40 marks

Min per mark: 1.5

Paper 1A (Multiple45m / 36 marks

Min per mark: 1.3

Paper 1B (Conventio105m / 84 marks

Min per mark: 1.3

Syllabus traceability

Topics linked to questions and mark weighting in this session

Instrumental analytical methods (Analytical Chemistry)

12 marks this session

Green Chemistry (Industrial Chemistry)

10 marks this session

Kinetics & Arrhenius equation (Industrial Chemistry)

10 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

LowHigh
Topic
2021
2022
2023
2024
2025
Σ

Enthalpy changes; Hess’s Law; energy cycles

12
12
24

Redox Reactions, Chemical Cells & Electrolysis

19
19

Reactions of Carbon Compounds (Inter-conversions)

18
18

Isomerism & Chemistry of Carbon Compounds

18
18

Homologous series; naming; addition polymerisation

14
14

Metals (Reactivity, displacement, extraction)

13
13

Reactions and Inter-conversions of Carbon Compounds

13
13

Instrumental analytical methods (Analytical Chemistry)

12
12

Paper comparison

Marks and duration breakdown across papers in this session

Paper 1A (Multiple Choice):

36 marks45 min

Paper 1B (Conventional):

84 marks105 min

Paper 2 (Elective Sections A & C):

40 marks60 min

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

Self-diagnostic checklist

Key actions before you sit this paper — copy and tick off as you revise

  • 1Message

    The 2024 Chemistry paper maintained a robust standard of assessment, showcasing a moderate-to-high difficulty level (3.8/5). Paper 1B (Conventional) demanded strong conceptual mastery, especially in topics like chemical cells and organic synthesis. Paper 2 (Electives) tested stud

  • 2Message

    The 2024 HKDSE Chemistry exam presented a highly balanced structure.

  • 3Message

    It tested core chemical concepts alongside challenging application questions, particularly in organic mechanisms, Arrhenius kinetics, and complex electrochemical cells.

  • 4Message

    Well-prepared students who excelled in precision of terminology and quantitative calculations achieved excellent results.

Teacher briefing pack

One-page session summary for tutors and classroom review

2024 2024

Chemistry

The 2024 HKDSE Chemistry exam presented a highly balanced structure. It tested core chemical concepts alongside challenging application questions, particularly in organic mechanisms, Arrhenius kinetics, and complex electrochemical cells. Well-prepared students who excelled in pre

  • The 2024 Chemistry paper maintained a robust standard of assessment, showcasing a moderate-to-high difficulty level (3.8/5). Paper 1B (Conventional) demanded strong conceptual mastery, especially in topics like chemical cells and organic synthesis. Paper 2 (Electives) tested stud

  • The 2024 HKDSE Chemistry exam presented a highly balanced structure.

  • It tested core chemical concepts alongside challenging application questions, particularly in organic mechanisms, Arrhenius kinetics, and complex electrochemical cells.

Total marks
160
Duration
210 min
Session difficulty
3.8 / 5
Level 5**
~95% of max
Level 5*
~91% of max
Level 5
~85% of max

Session analysis

The 2024 HKDSE Chemistry exam presented a highly balanced structure. It tested core chemical concepts alongside challenging application questions, particularly in organic mechanisms, Arrhenius kinetics, and complex electrochemical cells. Well-prepared students who excelled in precision of terminology and quantitative calculations achieved excellent results.

Updated Jun 11, 2026

Paper breakdown

Paper 1A (Multiple Choice):

36 marks45 min

Paper 1B (Conventional):

84 marks105 min

Paper 2 (Elective Sections A & C):

40 marks60 min

Top chapters

Instrumental analytical methods (Analytical Chemistry)12 marks
Green Chemistry (Industrial Chemistry)10 marks
Kinetics & Arrhenius equation (Industrial Chemistry)10 marks

Exam structure insights

Marks by chapter

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

Instrumental methods, forensic,12 marks
Catalysts; green chemistry (ato10 marks
Kinetics, activation energy; Ar10 marks
Reactions: substitution, additi10 marks
Reactivity series, displacement9 marks
Homologous series; naming; addi9 marks
Equilibrium constant (Kc); Le C9 marks
Enthalpy changes; Hess’s Law; e8 marks

Mark accessibility

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

78% within easy or medium reach

55
70
35
Easy: 55 marksMedium: 70 marksHard: 35 marks

Command word frequency

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

Explain18 times
Calculate10 times
Draw6 times
Suggest8 times
Describe5 times

Question type mix

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

160Marks
  • Structured & Computational

    72·14·45%

  • Elective Applied Questions

    40·6·25%

  • Multiple Choice

    36·36·23%

  • Chemical Essay

    12·2·8%

Study ROI

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

DifficultyRecurrence %Redox Reactions & …Acids and Bases Ti…Chemical Equilibri…Instrumental Analy…

Difficulty trend

Compare difficulty across recent years.

3.820213.820223.820233.82024

Time vs marks

Compare marks with suggested time allocation to plan exam pacing.

MarksMinutesMarks / min

Paper 1A (Multiple

0.80 m/min
36
45

Paper 1B (Conventio

0.80 m/min
84
105

Paper 2 (Elective S

0.67 m/min
40
60

Total marks

160

Total time

210 min

Avg pace

0.76

Exam tips

Paper format

Duration
1h
Total marks
40
Weighting
20%
Question types
Structured/Calculation Questions

Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.

CHEMISTRY/21 — HKDSE Chemistry (2024) | Revui