Structure
Connect the particulate nature of matter, atomic models, bonding, molecular shape, intermolecular forces, and classification to observed chemical and physical properties.
IB Sciences • HL
IB Chemistry HL
Use this IB Chemistry HL study guide to browse the syllabus topic structure, study materials, and practice resources.
Structured practice
IB Chemistry HL Question Bank
Jump straight into grouped unit practice without losing your place in the syllabus overview.
Structure 1. Models of the particulate nature of matter
S1.1 Introduction to the particulate nature of matter
S1.2 The nuclear atom
S1.3 Electron configurations
S1.4 Counting particles by mass: the mole
Structure 2. Models of bonding and structure
S2.1 The ionic model
S2.2 The covalent model
S2.2.1 Formation of covalent bonds
S2.2.2 Single, double and triple bonds
S2.2.3 Coordination bonds
S2.2.4 VSEPR theory
S2.2.5 Bond polarity
S2.2.6 Molecular polarity
S2.2.7 Covalent network structures
S2.2.8 Intermolecular forces
S2.2.9 Intermolecular forces and physical properties
S2.2.10 Chromatography
S2.2.11 Resonance structures (Higher Level Only)
S2.2.12 Benzene (Higher Level only)
S2.2.13 Expanded Octet of Electrons (Higher Level Only)
S2.2.14 Formal Charge and Lewis Formulas (Higher Level Only)
S2.2.15 Sigma and Pi Bonds (Higher Level Only)
S2.2.16 Hybridization and Bonding (Higher Level Only)
S2.3 The metallic model
Structure 3. Classification of matter
S3.1 The periodic table: classification of elements
S3.1.1 The structure of the periodic table
S3.1.2 Electron configuration and group trends
S3.1.3 Periodicity of properties
S3.1.4 Trends in chemical reactivity
S3.1.5 Metallic and non-metallic oxides
S3.1.6 Oxidation states
S3.1.7 Discontinuities in ionization energy trends (Higher Level Only)
S3.1.8 Properties of transition elements (Higher Level Only)
S3.1.9 Oxidations states of transition elements (Higher Level Only)
S3.1.10 Color of transition metal complexes (Higher Level Only)
S3.2 Functional groups: classification of organic compounds
S3.2.1 Representation of organic compounds
S3.2.2 Functional groups
S3.2.3 Homologous series
S3.2.4 Physical trends in homologous series
S3.2.5 IUPAC nomenclature
S3.2.6 Structural isomers
S3.2.7 Stereoisomers (Higher Level Only)
S3.2.8 Mass spectrometry (Higher Level Only)
S3.2.9 Infrared spectra (Higher Level Only)
S3.2.10 Proton nuclear magnetic resonance spectroscopy (Higher Level Only)
S3.2.11 H NMR spectra interpretation (Higher Level Only)
S3.2.12 Structural analysis (Higher Level Only)
Reactivity 1. What drives chemical reactions?
R1.1 Measuring enthalpy change
R1.2 Energy cycles in reactions
R1.3 Energy from fuels
Reactivity 2. How much, how fast and how far?
R2.1 How much? The amount of chemical change
R2.2 How fast? The rate of chemical change
R2.2.1 Rate of reaction
R2.2.2 Collision theory
R2.2.3 Factors affecting the rate of reaction
R2.2.4 Activation energy
R2.2.5 Catalysts
R2.2.6 Reaction mechanisms and rate-determining steps (Higher Level Only)
R2.2.7 Energy profiles and transition states (Higher Level Only)
R2.2.8 Molecularity (Higher Level Only)
R2.2.9 Rate equations (Higher Level Only)
R2.2.10 Order of a reaction (Higher Level Only)
R2.2.11 Rate constant (Higher Level Only)
R2.2.12 Arrhenius equation (Higher Level Only)
R2.2.13 Arrhenius factor (Higher Level Only)
R2.3 How far? The extent of chemical change
R2.3.1 Dynamic equilibrium
R2.3.2 The equilibrium law and constant
R2.3.3 Magnitude of K and temperature dependence
R2.3.4 Le Châtelier’s principle
R2.3.5 Reaction quotient (Q) (Higher Level Only)
R2.3.6 Quantifying equilibrium concentrations (Higher Level Only)
R2.3.7 Gibbs free energy and equilibrium (Higher Level Only)
Reactivity 3. What are the mechanisms of chemical change?
R3.1 Proton transfer reactions
R3.1.1 Brønsted–Lowry acid-base theory
R3.1.2 Conjugate acid-base pairs
R3.1.3 Amphiprotic species
R3.1.4 pH and the hydrogen ion concentration
R3.1.5 The ion product of water (Kw)
R3.1.6 Strong and weak acids and bases
R3.1.7 Neutralization reactions
R3.1.8 pH curves for neutralization
R3.1.9 pOH scale (Higher Level Only)
R3.1.10 Acid and base strength and constants (Higher Level Only)
R3.1.11 Conjugate Acid-Base pair (Higher Level Only)
R3.1.12 The pH of a salt solution (Higher Level only)
R3.1.13 pH curves of Acid-Base combinations (Higher Level Only)
R3.1.14 Acid-Base indicators and pH changes (Higher Level Only)
R3.1.15 Appropriate indicators for titration (Higher Level Only)
R3.1.16 Buffer solutions (Higher Level Only)
R3.1.17 The pH of a buffer solution (Higher Level Only)
R3.2 Electron transfer reactions
R3.2.1 Oxidation and reduction definitions
R3.2.2 Redox half-equations
R3.2.3 Reactivity of elements based on periodic trends
R3.2.4 Acid-metal reactions
R3.2.5 Electrochemical cells: Oxidation and reduction
R3.2.6 Primary (voltaic) cells
R3.2.7 Secondary (rechargeable) cells
R3.2.8 Electrolytic cells
R3.2.9 Oxidation of organic compounds
R3.2.10 Reduction of functional groups
R3.2.11 Reduction of unsaturated compounds
R3.2.12 Standard electrode potentials (Higher Level Only)
R3.2.13 Standard cell potential (Higher Level Only)
R3.2.14 Gibbs free energy and cell potential (Higher Level Only)
R3.2.15 Electrolysis of aqueous solutions (Higher Level Only)
R3.2.16 Electroplating (Higher Level Only)
R3.3 Electron sharing reactions
R3.4 Electron pair sharing reactions
R3.4.1 Nucleophiles
R3.4.2 Nucleophilic substitution reactions
R3.4.3 Heterolytic fission
R3.4.4 Electrophiles
R3.4.5 Electrophilic attack
R3.4.6 Lewis acid (Higher Level Only)
R3.4.7 Lewis acid-base reaction (Higher Level Only)
R3.4.8 Ligands and coordination bond (Higher Level Only)
R3.4.9 SN1 and SN2 mechanisms (Higher Level Only)
R3.4.10 Rate of the substitution reactions (Higher Level Only)
R3.4.11 Electrophilic addition (Higher Level only)
R3.4.12 The relative stability of carbocations (Higher Level Only)
R3.4.13 Reactions between benzene and electrophiles (Higher Level Only)
Overview
Course overview
How to study IB Chemistry HL
IB Chemistry HL is organised around two connected concepts: structure and reactivity. The current course began teaching in August or September 2023 and was first assessed in 2025. Strong revision moves between particulate models, observable evidence, symbolic equations, quantitative relationships, and practical data. HL adds greater depth and requires students to integrate standard-level and additional higher-level material across longer examinations.
Reactivity
Explain what drives reactions, how much and how fast change occurs, how equilibrium is established, and how reaction mechanisms account for evidence.
Inquiry and data
Interpret experimental design, raw and processed data, uncertainty, graphs, limitations, and improvements before drawing a chemically justified conclusion.
Assessment at a glance
For the current IB Chemistry HL course first assessed in 2025, external assessment contributes 80% and the scientific investigation contributes 20%. Calculators and a clean Chemistry data booklet are permitted for both external papers under the current guide.
| Component | Format | Weighting |
|---|---|---|
| Paper 1 | 2 hours; Paper 1A multiple choice and Paper 1B data/experimental questions | 36% |
| Paper 2 | 2 hours 30 minutes; short-answer and extended-response questions | 44% |
| Internal assessment | 10 hours; individual scientific investigation | 20% |
Sources: IB Chemistry guide (first assessment 2025) and official IB Chemistry course overview.
Revision plan
- 1.Map every topic from a structural model to a predicted property or pattern of reactivity.
- 2.Practise moving between words, particle diagrams, equations, graphs, and calculations without treating them as separate skills.
- 3.Use Paper 1B and practical questions to diagnose weaknesses in data analysis, uncertainty, and experimental reasoning.
- 4.Complete mixed Paper 1 and Paper 2 sets, then classify errors by concept, method, units, data-booklet use, or communication.
Exam strategy
Identify the species, model, and governing relationship before calculating. Use the data booklet deliberately, retain units and sensible precision, and explain the chemical reason behind any trend or observation. In longer responses, make the chain from structure to interaction to evidence explicit.
Practise IB Chemistry HL questionsFrequently asked questions
What does IB Chemistry HL cover?
IB Chemistry HL develops explanations of matter and chemical change through two organizing concepts: structure and reactivity. The course connects particulate models, bonding and classification with reaction drivers, extent, rate, and mechanisms, supported by practical and data-based work.
What syllabus applies to the current IB Chemistry course?
The current course began teaching in August or September 2023 and was first assessed in 2025. Students should confirm their examination session and any later guide updates with their school.
How is IB Chemistry HL assessed?
External assessment is worth 80%: Paper 1 lasts two hours and is worth 36%, while Paper 2 lasts two hours and 30 minutes and is worth 44%. The scientific investigation internal assessment is worth 20%.
What is in IB Chemistry HL Paper 1?
Paper 1 combines Paper 1A multiple-choice questions with Paper 1B data-based and experimental-work questions on standard-level and additional higher-level material. A calculator and clean Chemistry data booklet are required under the current guide.
What is the IB Chemistry scientific investigation?
The scientific investigation is the Chemistry internal assessment for both SL and HL. It is an individual investigation assessed across research design, data analysis, conclusion, and evaluation, and contributes 20% of the final subject result.