CHEMISTRY-II · CSAT (대학수학능력시험)
CHEMISTRY-II/11
Chemistry II
Chemistry II · 2021 · Variant 1
Relative difficulty
Analysis source: Korea Institute for Curriculum and Evaluation (KICE)
Analysis aligned to the official syllabus and assessment design.
4.0 / 5
50
30 min
Equilibrium shifts, rate laws, electrochemical cells, pH/buffer reasoning, and organic structure analysis.
Cohort performance
Session statistics from official examination reports
Total marks
50
Duration
30 min
Session difficulty
4.0 / 5
Calculator policy
No calculators in any CSAT section. All arithmetic must be done by hand. English includes a listening section with broadcast audio.
Key examiner messages
Top priorities from the principal examiner before you revise
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two…
KICE designs Chemistry II items from the national curriculum achievement standards and publishes all questions and answers after the exam.
EBS-linked items about 50% means concepts, source themes, or problem types are linked, but wording and contexts are commonly transformed.
The official timing is 30 min for 20 questions; pacing practice should match the actual OMR marking burden.
KICE publishes annual test-design directions (출제 방향) emphasising syllabus-faithful items, EBS textbook linkage (~50% of Korean, Mathematics, and English items), and post-2024 exclusion of extreme “killer” items outside public-education scope.
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
Cognitive skills emphasised in official test design.
Conceptual models
Weight: 30100%Quantitative problem solving
Weight: 30100%Graphical and experiment interpretation
Weight: 2583%Scientific reasoning
Weight: 1550%
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
Equilibrium: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your o…
Kinetics: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; transformed…
Electrochemistry: Losing marks on easy items because time was spent on one high-difficulty question. — Use a two-pass strategy and mark u…
Organic chemistry: Eliminating options based on a keyword match rather than the full causal relationship. — Check subject, time period, d…
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
Official body
Korea Institute for Curriculum and Evaluation (KICE)
Grading system
KICE standard score (mean 50, SD 10; range 0–100) with percentile and Grade 1–9 bands
Scale band
Std score
Scale band
Percentile
Scale band
1
Scale band
2
Deep insights
What top candidates did
Techniques and approaches examiners rewarded in this series
1. Start from the model
Chemistry II items usually become easier once the physical, chemical, biological, or earth-system model is named. Write the law, cycle, or mechanism before substituting numbers.
2. Annotate every diagram
Label axes, units, directions, phases, and variables in equilibrium tables, rate curves, cell diagrams, and organic structures. Most upper-level distractors come from reading a diagram too quickly.
3. Link formulas to meaning
For K expressions, rate relationships, Nernst-style reasoning, and acid-base equilibria, memorize what each symbol represents and the condition where the formula applies, not only the algebraic form.
4. Treat experiments as arguments
In kinetics and equilibrium experiments questions, identify hypothesis, control, independent variable, dependent variable, and conclusion before choosing.
5. Use dimensional checks
When a numeric answer appears plausible, check units and order of magnitude. This catches most coefficient and power-of-ten errors.
Command word playbook
How to match each command word to the expected response style
No data available in official reports
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
Thermochemistry, entropy/free energy, reaction rates, and catalysts
Official topic weighting
Chemical equilibrium
Official topic weighting
Le Chatelier principle, acid-base equilibrium, buffers
Official topic weighting
Electrochemistry: cells, electrolysis, redox potentials
Official topic weighting
Organic chemistry, polymers, materials, and molecular structure
Official topic weighting
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 equilibrium, Le Chatelier principle, acid-base equilibrium, buffers
Organic chemistry, polymers, materials, and molecular structure
Thermochemistry, entropy/free energy, reaction rates, and catalysts
Electrochemistry: cells, electrolysis, redox potentials
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
Chemistry II: 20 multiple-choice science inquiry questions
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
Thermochemistry, entropy/free energy, reaction rates, and catalysts
Official topic weighting
Practise in RevuiChemical equilibrium
Official topic weighting
Practise in RevuiLe Chatelier principle, acid-base equilibrium, buffers
Official topic weighting
Practise in RevuiElectrochemistry: cells, electrolysis, redox potentials
Official topic weighting
Practise in RevuiOrganic chemistry, polymers, materials, and molecular structure
Official topic weighting
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two…
- 2Message
KICE designs Chemistry II items from the national curriculum achievement standards and publishes all questions and answers after the exam.
- 3Message
EBS-linked items about 50% means concepts, source themes, or problem types are linked, but wording and contexts are commonly transformed.
- 4Message
The official timing is 30 min for 20 questions; pacing practice should match the actual OMR marking burden.
- 5Message
KICE publishes annual test-design directions (출제 방향) emphasising syllabus-faithful items, EBS textbook linkage (~50% of Korean, Mathematics, and English items), and post-2024 exclusion of extreme “killer” items outside public-education scope.
- 6Pitfall
Equilibrium: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your o…
- 7Pitfall
Kinetics: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; transformed…
- 8Pitfall
Electrochemistry: Losing marks on easy items because time was spent on one high-difficulty question. — Use a two-pass strategy and mark u…
- 9Pitfall
Organic chemistry: Eliminating options based on a keyword match rather than the full causal relationship. — Check subject, time period, d…
- 10Strength
1. Start from the model: Chemistry II items usually become easier once the physical, chemical, biological, or earth-system mo
- 11Strength
2. Annotate every diagram: Label axes, units, directions, phases, and variables in equilibrium tables, rate curves, cell diagra
- 12Strength
3. Link formulas to meaning: For K expressions, rate relationships, Nernst-style reasoning, and acid-base equilibria, memorize wh
Teacher briefing pack
One-page session summary for tutors and classroom review
2021 2021
Chemistry II
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two in
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two…
KICE designs Chemistry II items from the national curriculum achievement standards and publishes all questions and answers after the exam.
EBS-linked items about 50% means concepts, source themes, or problem types are linked, but wording and contexts are commonly transformed.
Equilibrium: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your o…
Kinetics: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; transformed…
- Total marks
- 50
- Duration
- 30 min
- Session difficulty
- 4.0 / 5
- Calculator policy
- No calculators in any CSAT section. All arithmetic must be done by hand. English includes a listening section with broadcast audio.
Session analysis
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inquiry subjects and EBS linkage around 50%. Korea Institute for Curriculum and Evaluation (KICE) emphasises equilibrium shifts, rate laws, electrochemical cells, ph/buffer reasoning, and organic structure analysis.. Priority revision: Thermochemistry, entropy/free energy, reaction rates, and catalysts, Chemical equilibrium, Le Chatelier principle, acid-base equilibrium, buffers, Electrochemistry: cells, electrolysis, redox potentials, Organic chemistry, polymers, materials, and molecular structure. Chemistry II items usually become easier once the physical, chemical, biological, or earth-system model is named. Write the law, cycle, or mechanism before substituting numbers.
Updated 2026-07-03
Paper breakdown
Chemistry II: 20 multiple-choice science inquiry questions
Top chapters
Exam structure insights
Marks by syllabus topic
Revision priority from official test-design weighting.
Mark accessibility
Estimated difficulty spread based on official design.
Equilibrium shifts, rate laws, electrochemical cells, pH/buffer reasoning, and o
Paper structure
Official paper breakdown for this subject.
Chemistry II
50·10·100%
Official syllabus scope
KICE Chemistry II assesses thermodynamics, reaction rates, chemical equilibrium, acid-base equilibrium, electrochemistry, organic chemistry, and advanced materials. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inquiry subjects and EBS linkage around 50%.
Difficulty verdict
Rated 4/5 for November sessions. Equilibrium shifts, rate laws, electrochemical cells, pH/buffer reasoning, and organic structure analysis.
What examiners measure
1. Apply equilibrium, kinetics, thermodynamics, and electrochemical principles quantitatively. 2. Interpret rate graphs, equilibrium tables, pH data, and cell diagrams. 3. Analyze organic structures, functional groups, isomers, and reaction pathways. 4. Connect molecular structure to material properties and industrial processes. 5. Evaluate experiments using particle-level explanations.
Where the marks are
Highest-weight syllabus areas: Thermochemistry, entropy/free energy, reaction rates, and catalysts; Chemical equilibrium, Le Chatelier principle, acid-base equilibrium, buffers; Electrochemistry: cells, electrolysis, redox potentials; Organic chemistry, polymers, materials, and molecular structure.
Examiner notes & key calculations
- KICE designs Chemistry II items from the national curriculum achievement standards and publishes all questions and answers after the exam.
- EBS-linked items about 50% means concepts, source themes, or problem types are linked, but wording and contexts are commonly transformed.
- The official timing is 30 min for 20 questions; pacing practice should match the actual OMR marking burden.
- Distractors usually represent common misconceptions, not random wrong answers, so elimination must be evidence-based.
- High-discrimination items often combine two syllabus domains or require interpreting a new source, graph, table, or scenario.
- A full mock should include answer-sheet transfer and a post-test error log organized by domain and mistake type.
- Chemistry II uses graphs, diagrams, experiments, and model-based reasoning more than isolated factual recall.
- Science inquiry timing is tight; students should know which diagrams or calculations can be completed in under one minute.
- Paper 1: Chemistry II · 50 marks · 30 min · 20 multiple-choice science inquiry questions.
Exam tips
Paper format
- Duration
- 30 min
- Total marks
- 50
- Weighting
- 100%
- Question types
- 20 multiple-choice science inquiry questions
- Chemistry II items usually become easier once the physical, chemical, biological, or earth-system model is named. Write the law, cycle, or mechanism before substituting numbers.
- Label axes, units, directions, phases, and variables in equilibrium tables, rate curves, cell diagrams, and organic structures. Most upper-level distractors come from reading a diagram too quickly.
- For K expressions, rate relationships, Nernst-style reasoning, and acid-base equilibria, memorize what each symbol represents and the condition where the formula applies, not only the algebraic form.
Common mistakes
Equilibrium
Answering from memory before checking the condition in the stem.
How to avoid: Underline the limiting condition and restate it in your own words before selecting an option.
Kinetics
Treating a familiar source, graph, or scenario as identical to a past EBS example.
How to avoid: Compare variables and wording; transformed linkage often changes the required inference.
Electrochemistry
Losing marks on easy items because time was spent on one high-difficulty question.
How to avoid: Use a two-pass strategy and mark unresolved items after 60-75 seconds.
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.