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CHEMISTRY · IB Diploma Programme

CHEMISTRY/21

Paper 2

Chemistry · 2023 · Variant 1

Relative difficulty

Demanding · 3.5/5

Analysis source: International Baccalaureate Organization

Analysis aligned to the official syllabus and assessment design.

Relative difficulty

3.5 / 5

Total marks

115

Duration

180 min

Most tested topic

Electron transfer reactions

Cohort performance

Session statistics from official examination reports

Total marks

115

Duration

180 min

Session difficulty

3.5 / 5

Key examiner messages

Top priorities from the principal examiner before you revise

1

The May 2023 Standard Level examination represents a balanced yet demanding assessment.

2

Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

3

Compare difficulty across recent years. Compare topic weight by year to spot recurring and returning areas.

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

Analytical Thinking8
Mathematical6
Spatial5
Drawing & Interpretation4
Experimental3
Conceptual Explanation2

Skill weighting

Shows the skill mix this paper tested most heavily.

Analytical ThinkingAnalyticalThinkingMathematicalMathematicalSpatialSpatialDrawing & InterpretationDrawing &InterpretationExperimentalExperimentalConceptual ExplanationConceptualExplanation
SkillWeightShare
  • Analytical Thinking

    Weight: 8100%
  • Mathematical

    Weight: 675%
  • Spatial

    Weight: 563%
  • Drawing & Interpretation

    Weight: 450%
  • Experimental

    Weight: 338%
  • Conceptual Explanation

    Weight: 225%

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

IB subject report — grade distributions, IA weighting, and HL/SL distinctions

Level 7

Excellent — top band for competitive university offers

Level 6

Very good — strong HL performance

Level 5

Good — solid pass at higher level

Level 4

Satisfactory — minimum for many university credits

Level 3

Mediocre

Level 2

Poor

Level 1

Very poor

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: 15

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

OutlineFrequency: 12

Match the expected response style for “Outline” questions.

StateFrequency: 10

Match the expected response style for “State” questions.

DeduceFrequency: 9

Match the expected response style for “Deduce” questions.

CalculateFrequency: 8

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

IdentifyFrequency: 6

Name or point to the specific feature asked for — avoid extra explanation.

SketchFrequency: 5

Match the expected response style for “Sketch” questions.

FormulateFrequency: 4

Match the expected response style for “Formulate” questions.

Time traps

Sections where candidates spent disproportionate time relative to marks

Paper 3 Section B (35m / 20 marks

Min per mark: 1.8

Paper 3 Section A (25m / 15 marks

Min per mark: 1.7

Paper 1 (Standard L45m / 30 marks

Min per mark: 1.5

Paper 2 (Standard L75m / 50 marks

Min per mark: 1.5

Syllabus traceability

Topics linked to questions and mark weighting in this session

Electron transfer reactions

14 marks this session

The periodic table: Classification of elements

11 marks this session

The covalent model

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
2023
2024
2025
Σ

Counting particles by mass: The mole

11
13
24

Green Chemistry and Experimental Methods

23
23

Option D: Medicinal Chemistry

20
20

The covalent model

10
10
20

Measurements, Uncertainties and Spectroscopy

14
14

Electron transfer reactions

14
14

How fast? The rate of chemical change

13
13

Functional groups: Classification of organic compounds

12
12

Paper comparison

Marks and duration breakdown across papers in this session

Paper 1 (Standard Level):

30 marks45 min

Paper 2 (Standard Level):

50 marks75 min

Paper 3 (Standard Level):

35 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 May 2023 Standard Level examination represents a balanced yet demanding assessment.

  • 2Message

    Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

  • 3Message

    Compare difficulty across recent years. Compare topic weight by year to spot recurring and returning areas.

Teacher briefing pack

One-page session summary for tutors and classroom review

2023 2023

Chemistry

The May 2023 Standard Level examination represents a balanced yet demanding assessment. Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

  • The May 2023 Standard Level examination represents a balanced yet demanding assessment.

  • Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

  • Compare difficulty across recent years. Compare topic weight by year to spot recurring and returning areas.

Total marks
115
Duration
180 min
Session difficulty
3.5 / 5

Session analysis

The May 2023 Standard Level examination represents a balanced yet demanding assessment. Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

Updated Jun 14, 2026

Paper breakdown

Paper 1 (Standard Level):

30 marks45 min

Paper 2 (Standard Level):

50 marks75 min

Paper 3 (Standard Level):

35 marks60 min

Top chapters

Electron transfer reactions14 marks
The periodic table: Classification of elements11 marks
The covalent model10 marks

Exam structure insights

Marks by chapter

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

Electron transfer reactions14 marks
The periodic table: Classificat11 marks
The covalent model10 marks
Counting particles by mass: The9 marks
Proton transfer reactions9 marks
Functional groups: Classificati8 marks
Measuring enthalpy change7 marks
Introduction to the particulate6 marks

Mark accessibility

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

78% within easy or medium reach

35
55
25
Easy: 35 marksMedium: 55 marksHard: 25 marks

Command word frequency

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

Explain15 times
Outline12 times
State10 times
Deduce9 times
Calculate8 times
Identify6 times
Sketch5 times
Formulate4 times

Question type mix

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

115Marks
  • shortAnswer

    65·23·57%

  • multipleChoice

    30·30·26%

  • calculation

    14·6·12%

  • structuralDrawing

    6·4·5%

Study ROI

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

DifficultyRecurrence %Electron transfer …Counting particles…Functional groups:…Proton transfer re…The periodic table…

Difficulty trend

Compare difficulty across recent years.

3.82021420223.52023

Time vs marks

Compare marks with suggested time allocation to plan exam pacing.

MarksMinutesMarks / min

Paper 1 (Standard L

0.67 m/min
30
45

Paper 2 (Standard L

0.67 m/min
50
75

Paper 3 Section A (

0.60 m/min
15
25

Paper 3 Section B (

0.57 m/min
20
35

Total marks

115

Total time

180 min

Avg pace

0.64

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.

02958861157 estimated6 estimated5 estimated4 estimated3 estimated2 estimated1 estimated303653576169808895106115

Next-year prediction

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

Ideal gases

85%

85%

How far? The extent of chemical change

80%

80%

The metallic model

75%

75%

May 2023 IB Chemistry SL Analysis

The May 2023 Standard Level examination represents a balanced yet demanding assessment. Spanning core principles of physical, inorganic, and organic chemistry, this paper pair rewards students who possess both qualitative conceptual precision and rigorous quantitative execution.

Exam tips

Paper format

Duration
2h 30min
Total marks
90

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

CHEMISTRY/21 — IB Diploma Programme Chemistry (2023) | Revui