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CHEMISTRY-I · CSAT (대학수학능력시험)

CHEMISTRY-I/11

Chemistry I

Chemistry I · 2022 · Variant 1

Relative difficulty

Demanding · 4.0/5

Analysis source: Korea Institute for Curriculum and Evaluation (KICE)

Analysis aligned to the official syllabus and assessment design.

Relative difficulty

4.0 / 5

Total marks

50

Duration

30 min

Most tested topic

Mole-ratio calculations, periodic trends, bonding, titration, and redox reasoning.

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

1

KICE Chemistry I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inqu…

2

KICE designs Chemistry I items from the national curriculum achievement standards and publishes all questions and answers after the exam.

3

EBS-linked items about 50% means concepts, source themes, or problem types are linked, but wording and contexts are commonly transformed.

4

The official timing is 30 min for 20 questions; pacing practice should match the actual OMR marking burden.

5

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

Use mole concepts, equations, and concentration relationships accurately.
Explain atomic structure, electron configuration, periodic trends, and bonding.
Analyze acid-base, oxidation-reduction, and solution reactions.
Interpret particle models, graphs, titration data, and experimental observations.
Connect chemical principles to materials and life contexts.

Skill weighting

Cognitive skills emphasised in official test design.

Conceptual modelsConceptualmodelsQuantitative problem solvingQuantitativeproblem solvingGraphical and experiment interpretationGraphical andexperimentScientific reasoningScientificreasoning
SkillWeightShare
  • 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

Stoichiometry: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your…

2024 20242023 20232021 20212020 20204 sessions

Periodic trends: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; tran…

2024 20242023 20232021 20212020 20204 sessions

Acid-base and redox: Losing marks on easy items because time was spent on one high-difficulty question. — Use a two-pass strategy and mar…

2024 20242023 20232021 20212020 20204 sessions

Particle models: Eliminating options based on a keyword match rather than the full causal relationship. — Check subject, time period, dir…

2024 20242023 20232021 20212020 20204 sessions

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 I 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 particle diagrams, titration curves, and periodic tables. Most upper-level distractors come from reading a diagram too quickly.

3. Link formulas to meaning

For mole ratios, molarity, charge balance, pH, and oxidation numbers, memorize what each symbol represents and the condition where the formula applies, not only the algebraic form.

4. Treat experiments as arguments

In reaction observations and variable-control lab prompts 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

Matter, atoms, electron configuration, periodic table, and bonding

Official topic weighting

Moles, formulas, equations, stoichiometry, gases, and solutions

Official topic weighting

Acid-base reactions, neutralization, redox, and chemical energetics

Official topic weighting

Chemical materials and everyday/life applications

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

LowHigh
Topic
2020
2021
2022
2023
2024
Σ

Moles, formulas, equations, stoichiometry, gases, and solutions

16
16
16
16
16
80

Acid-base reactions, neutralization, redox, and chemical energetics

14
14
14
14
14
70

Matter, atoms, electron configuration, periodic table, and bonding

13
13
13
13
13
65

Chemical materials and everyday/life applications

7
7
7
7
7
35

Difficulty trend

How session difficulty has shifted across recent years

20202021202220232024
2020 2020 · 4.0/52021 2021 · 4.0/52022 2022 · 4.0/52023 2023 · 4.0/52024 2024 · 4.2/5

Paper comparison

Marks and duration breakdown across papers in this session

Chemistry I: 20 multiple-choice science inquiry questions

50 marks30 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

    KICE Chemistry I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inqu…

  • 2Message

    KICE designs Chemistry I 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

    Stoichiometry: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your…

  • 7Pitfall

    Periodic trends: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; tran…

  • 8Pitfall

    Acid-base and redox: Losing marks on easy items because time was spent on one high-difficulty question. — Use a two-pass strategy and mar…

  • 9Pitfall

    Particle models: Eliminating options based on a keyword match rather than the full causal relationship. — Check subject, time period, dir…

  • 10Strength

    1. Start from the model: Chemistry I items usually become easier once the physical, chemical, biological, or earth-system mod

  • 11Strength

    2. Annotate every diagram: Label axes, units, directions, phases, and variables in particle diagrams, titration curves, and per

  • 12Strength

    3. Link formulas to meaning: For mole ratios, molarity, charge balance, pH, and oxidation numbers, memorize what each symbol repr

Teacher briefing pack

One-page session summary for tutors and classroom review

2022 2022

Chemistry I

KICE Chemistry I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inquiry

  • KICE Chemistry I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. The 2024 CSAT science inquiry format is 20 questions, 30 minutes, 50 points, with candidates selecting up to two inqu…

  • KICE designs Chemistry I 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.

  • Stoichiometry: Answering from memory before checking the condition in the stem. — Underline the limiting condition and restate it in your…

  • Periodic trends: Treating a familiar source, graph, or scenario as identical to a past EBS example. — Compare variables and wording; tran…

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 I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. 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 mole-ratio calculations, periodic trends, bonding, titration, and redox reasoning.. Priority revision: Matter, atoms, electron configuration, periodic table, and bonding, Moles, formulas, equations, stoichiometry, gases, and solutions, Acid-base reactions, neutralization, redox, and chemical energetics, Chemical materials and everyday/life applications. Chemistry I 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 I: 20 multiple-choice science inquiry questions

50 marks30 min

Top chapters

Matter, atoms, electron configuration, periodic table, and bonding13 marks
Moles, formulas, equations, stoichiometry, gases, and solutions16 marks
Acid-base reactions, neutralization, redox, and chemical energetics14 marks
Chemical materials and everyday/life applications7 marks

Exam structure insights

Marks by syllabus topic

Revision priority from official test-design weighting.

Matter, atoms, electron configuratio13 marks
Moles, formulas, equations, stoichio16 marks
Acid-base reactions, neutralization,14 marks
Chemical materials and everyday/life7 marks

Mark accessibility

Estimated difficulty spread based on official design.

Mole-ratio calculations, periodic trends, bonding, titration, and redox reasonin

23
46
31
Easy: 23 marksMedium: 46 marksHard: 31 marks

Paper structure

Official paper breakdown for this subject.

50Marks
  • Chemistry I

    50·10·100%

Official syllabus scope

KICE Chemistry I assesses atomic structure, periodicity, chemical bonding, stoichiometry, solutions, acid-base reactions, redox, and everyday chemical systems. 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. Mole-ratio calculations, periodic trends, bonding, titration, and redox reasoning.

What examiners measure

1. Use mole concepts, equations, and concentration relationships accurately. 2. Explain atomic structure, electron configuration, periodic trends, and bonding. 3. Analyze acid-base, oxidation-reduction, and solution reactions. 4. Interpret particle models, graphs, titration data, and experimental observations. 5. Connect chemical principles to materials and life contexts.

Where the marks are

Highest-weight syllabus areas: Matter, atoms, electron configuration, periodic table, and bonding; Moles, formulas, equations, stoichiometry, gases, and solutions; Acid-base reactions, neutralization, redox, and chemical energetics; Chemical materials and everyday/life applications.

Examiner notes & key calculations

  • KICE designs Chemistry I 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 I 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 I · 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 I 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 particle diagrams, titration curves, and periodic tables. Most upper-level distractors come from reading a diagram too quickly.
  • For mole ratios, molarity, charge balance, pH, and oxidation numbers, memorize what each symbol represents and the condition where the formula applies, not only the algebraic form.

Common mistakes

  • Stoichiometry

    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.

  • Periodic trends

    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.

  • Acid-base and redox

    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.

CHEMISTRY-I/11 — CSAT (대학수학능력시험) Chemistry I (2022) | Revui