The Complete IB Chemistry Syllabus: SL and HL


IB Chemistry is tough. If you are reading this syllabus, I assume you are interested in potentially taking this course or you are currently enrolled in the course. In this article, I'll discuss every topic covered in IB Chemistry Standard Level and IB Chemistry Higher Level , the number of hours dedicated to each topic, and the practical work and assessments you’ll have to complete for the course. I’ll also explain the changes coming to IB Chemistry in August 2023.


2023 IB Chemistry Changes

IB Chemistry is changing in August 2023, and the first assessment will take place in May 2025. All of the information in this article comes directly from the IB’s website and updated IB Chemistry subject brief. However, the full course syllabus isn’t out yet, so there’s still a lot of information that’s unavailable—like the learning goals and specific content points students will need to know for each topic. 

Rest assured, though, we’ve followed the IB Chemistry subject brief and updates to a T to give you an accurate overview of the changes and the new course outline. As soon as the rest of the details become available, we’ll add those, too! 

So without further ado, let’s get started with the changes to the course.

The biggest change to IB Chemistry is the amount of content included in the course. The new IB Chemistry has significantly reduced the content load, and so more time will be spent on the concepts included to build deeper knowledge. 

In the past, students all covered core topics according to the SL or HL breakdown, and then they selected an additional option topic (like materials or medicinal chemistry). The new syllabus has removed the additional option topics and, instead, includes some of those materials in either the standard level or higher level subtopics that all students will complete.

Another change to IB Chemistry is the emphasis placed on skill development and understandings that connect factual, procedural, and metacognitive knowledge. The IB wants students to see how important it is to connect learning with conceptual understanding, and so the course will be an ongoing process of building understanding, spotting misconceptions, and adding new knowledge. This method of conceptual understanding will help students become aware and critical of their own knowledge and skills, and they’ll be able to transfer them to new concepts in different ways.

Lastly, the IB has made a few changes to the assessment model of IB Chemistry. For external assessments, all students will take only 2 examinations: Paper 1, which is divided into 1A  and 1B sections, and Paper 2. 

Internal assessment has also changed slightly. Where the old syllabus required students to work alone on their ‘individual investigation’ (lab project and a report), the new syllabus encourages students to collaborate in small groups to support one another (hence the change to ‘scientific investigation’). Students must still submit an individual report (that is unique to each student), but they will be able to share their methodologies when conducting their lab projects.


Skills in the Study of Chemistry

Because chemistry is practical in nature, the IB emphasizes skills and techniques that students will learn and practice, called approaches to learning. Students will build these skills by using specific tools throughout the course. Ultimately, students will become comfortable and knowledgeable with the tools, expand their skills, and grow their abilities to inquire information in different ways—called inquiry processes. 


Approaches to Learning

  • Thinking skills
  • Research skills
  • Self-management skills
  • Communication skills
  • Social skills



  • Experimental techniques
  • Technology
  • Mathematics


Inquiry Process

  • Exploring and designing
  • Collecting and processing data
  • Concluding and evaluating


IB Chemistry SL and HL Core

Both IB Chemistry SL and HL cover all structures and topics—the only exception is Reactivity 1.4 (Entropy and spontaneity), which includes additional content for HL students. The major difference between SL and HL is the amount of hours dedicated to the programme’s core: SL covers 110 hours and HL covers 180.

The curriculum is divided into two organizing concepts: structure and reactivity. Structure refers to the nature of matter from simple to more complex forms, and reactivity refers to how and why chemical reactions occur. 

In the guide table below, notice that the structure and reactivity concepts are subdivided further into subtopics. It might be helpful to think of the broad structures and reactions as umbrellas (overarching, unique subject-specific concepts) and their subtopics as smaller ideas that each fall under those bigger concepts. 


Structure #1: Models of the Particular Nature of Matter—17 Hours for SL and 21 Hours for HL

Subtopic Number
IB Points to Understand 
Structure 1.1
Introduction to the particular nature of matter
Structure 1.2
The nuclear atom
Structure 1.3
Electron configurations
Structure 1.4
Counting particles by mass: The mole
Structure 1.5
Ideal gases



Structure #2: Models of Bonding and Structure—20 Hours for SL and 30 Hours for HL

Subtopic Number
IB Points to Understand
Structure 2.1
The ionic model
Structure 2.2
The covalent model
Structure 2.3
The metallic model
Structure 2.4
From models to materials


Structure #3: Classification of Matter—16 Hours for SL and 31 Hours for HL

Subtopic Number
IB Points to Understand
Structure 3.1
The periodic table: Classification of elements
Structure 3.2
Functional groups: Classification of organic compounds

Reactivity #1: What Drives Chemical Reactions?—12 Hours for SL and 22 Hours for HL

Subtopic Number
IB Points to Understand
Reactivity 1.1
Measuring enthalpy change
Reactivity 1.2
Energy cycles in reactions
Reactivity 1.3
Energy from fuels
Reactivity 1.4
Entropy and spontaneity (additional HL content)



Reactivity #2: How Much, How Fast and How Far?—21 Hours for SL and 31 Hours for HL

Subtopic Number
IB Topics to Understand
Reactivity 2.1
How much? The amount of chemical change
Reactivity 2.2
How fast? The rate of chemical change
Reactivity 2.3
How far? The extent of chemical change



Experimental Programme: 40 Hours for SL and 60 Hours for HL 

Programme Task 
Practical work
Collaborative sciences project
Scientific investigation




Topic #11: Measurement and Data Processing—10 Hours for SL and HL

Subtopic Subtopic Number IB Points to Understand
Uncertainties and errors in measurement and results 11.1
  • "Qualitative data includes all non-numerical information obtained from observations not from measurement."
  • "Quantitative data are obtained from measurements, and are always associated with random errors/uncertainties, determined by the apparatus, and by human limitations such as reaction times."
  • "Propagation of random errors in data processing shows the impact of the uncertainties on the final result."
  • "Experimental design and procedure usually lead to systematic errors in measurement, which cause a deviation in a particular direction."
  • "Repeat trials and measurements will reduce random errors but not systematic errors."
Graphical techniques 11.2
  • "Graphical techniques are an effective means of communicating the effect of an independent variable on a dependent variable, and can lead to determination of physical quantities."
  • "Sketched graphs have labeled but unscaled axes, and are used to show qualitative trends, such as variables that are proportional or inversely proportional."
  • "Drawn graphs have labeled and scaled axes, and are used in quantitative measurements."
Spectroscopic identification of organic compounds 11.3
  • "The degree of unsaturation or index of hydrogen deficiency (IHD) can be used to determine from a molecular formula the number of rings or multiple bonds in a molecule."
  • "Mass spectrometry (MS), proton nuclear magnetic resonance spectroscopy (1H NMR) and infrared spectroscopy (IR) are techniques that can be used to help identify compounds and to determine their structure."



Additional Higher Level Topics

These topics (a total of 60 hours) are only for Higher Level students.


Atomic Structure—2 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Electrons in atoms (HL ONLY) 12.1
  • "In an emission spectrum, the limit of convergence at higher frequency corresponds to the first ionization energy."
  • "Trends in first ionization energy across periods account for the existence of main energy levels and sub-levels in atoms."
  • "Successive ionization energy data for an element give information that shows relations to electron configurations."



The Periodic Table: Transition Metals—4 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
First-row d-block elements (HL ONLY) 13.1
  • "Transition elements have variable oxidation states, form complex ions with ligands, have coloured compounds, and display catalytic and magnetic properties."
  • "Zn is not considered to be a transition element as it does not form ions with incomplete d-orbitals."
  • "Transition elements show an oxidation state of +2 when the s-electrons are removed."
Coloured complexes (HL ONLY) 13.2
  • "The d sub-level splits into two sets of orbitals of different energy in a complex ion."
  • "Complexes of d-block elements are coloured, as light is absorbed when an electron is excited between the d-orbitals."
  • "The colour absorbed is complementary to the colour observed."





Chemical Bonding and Structure—7 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Further aspects of covalent bonding and structure (HL ONLY) 14.1
  • "Covalent bonds result from the overlap of atomic orbitals. A sigma bond (σ) is formed by the direct head-on/end-to-end overlap of atomic orbitals, resulting in electron density concentrated between the nuclei of the bonding atoms. A pi bond (π) is formed by the sideways overlap of atomic orbitals, resulting in electron density above and below the plane of the nuclei of the bonding atoms."
  • "Formal charge (FC) can be used to decide which Lewis (electron dot) structure is preferred from several. The FC is the charge an atom would have if all atoms in the molecule had the same electronegativity. FC = (Number of valence electrons)-½(Number of bonding electrons)-(Number of non-bonding electrons). The Lewis (electron dot) structure with the atoms having FC values closest to zero is preferred."
  • "Exceptions to the octet rule include some species having incomplete octets and expanded octets."
  • "Delocalization involves electrons that are shared by/between all atoms in a molecule or ion as opposed to being localized between a pair of atoms."
  • "Resonance involves using two or more Lewis (electron dot) structures to represent a particular molecule or ion. A resonance structure is one of two or more alternative Lewis (electron dot) structures for a molecule or ion that cannot be described fully with one Lewis (electron dot) structure alone."
Hybridization (HL ONLY) 14.2
  • "A hybrid orbital results from the mixing of different types of atomic orbitals on the same atom."



Energetics/Thermochemistry—7 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Energy cycles (HL ONLY) 15.1
  • "Representative equations (eg M+(g) → M+(aq)) can be used for enthalpy/energy of hydration, ionization, atomization, electron affinity, lattice, covalent bond and solution."
  • "Enthalpy of solution, hydration enthalpy and lattice enthalpy are related in an energy cycle."
Entropy and spontaneity (HL ONLY) 15.2
  • "Entropy (S) refers to the distribution of available energy among the particles. The more ways the energy can be distributed the higher the entropy."
  • "Gibbs free energy (G) relates the energy that can be obtained from a chemical reaction to the change in enthalpy (ΔH), change in entropy (ΔS), and absolute temperature (T)."
  • "Entropy of gas>liquid>solid under same conditions."


Chemical Kinetics—6 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Rate expression and reaction mechanism (HL ONLY) 16.1
  • "Reactions may occur by more than one step and the slowest step determines the rate of reaction (rate determining step/RDS)."
  • "The molecularity of an elementary step is the number of reactant particles taking part in that step."
  • "The order of a reaction can be either integer or fractional in nature. The order of a reaction can describe, with respect to a reactant, the number of particles taking part in the rate-determining step."
  • "Rate equations can only be determined experimentally."
  • "The value of the rate constant (k) is affected by temperature and its units are determined from the overall order of the reaction."
  • "Catalysts alter a reaction mechanism, introducing a step with lower activation energy."

Activation energy (HL ONLY)

  • "The Arrhenius equation uses the temperature dependence of the rate constant to determine the activation energy."
  • "A graph of 1/T against ln k is a linear plot with gradient – Ea / R and intercept, lnA."
  • "The frequency factor (or pre-exponential factor) (A) takes into account the frequency of collisions with proper orientations."





Equilibrium—4 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
The equilibrium law (HL ONLY) 17.1
  • "Le Châtelier's principle for changes in concentration can be explained by the equilibrium law."
  • "The position of equilibrium corresponds to a maximum value of entropy and a minimum in the value of the Gibbs free energy."
  • "The Gibbs free energy change of a reaction and the equilibrium constant can both be used to measure the position of an equilibrium reaction and are related by the equation, ∆G° = −RT ln(𝐾)"



Acids and Bases—10 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Lewis acids and bases (HL ONLY) 18.1
  • "A Lewis acid is a lone pair acceptor and a Lewis base is a lone pair donor."
  • "When a Lewis base reacts with a Lewis acid a coordinate bond is formed."
  • "A nucleophile is a Lewis base and an electrophile is a Lewis acid."
Calculations involving acids and bases (HL ONLY) 18.2
  • "The expression for the dissociation constant of a weak acid (Ka) and a weak base (Kb)."
  • "For a conjugate acid base pair, Ka × Kb = Kw."
  • "The relationship between Ka and pKa is (pKa = -log Ka), and between Kb and pKb is (pKb = -log Kb)."
pH curves (HL ONLY) 18.3
  • "The characteristics of the pH curves produced by the different combinations of strong and weak acids and bases."
  • "An acid–base indicator is a weak acid or a weak base where the components of the conjugate acid–base pair have different colours."
  • "The relationship between the pH range of an acid–base indicator, which is a weak acid, and its pKa value."
  • "The buffer region on the pH curve represents the region where small additions of acid or base result in little or no change in pH."
  • "The composition and action of a buffer solution."



Redox Processes—6 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Electrochemical cells (HL ONLY) 19.1
  • "A voltaic cell generates an electromotive force (EMF) resulting in the movement of electrons from the anode (negative electrode) to the cathode (positive electrode) via the external circuit. The EMF is termed the cell potential (Eº)."
  • "The standard hydrogen electrode (SHE) consists of an inert platinum electrode in contact with 1 mol dm-3 hydrogen ion and hydrogen gas at 100 kPa and 298 K. The standard electrode potential (Eº) is the potential (voltage) of the reduction half-equation under standard conditions measured relative to the SHE. Solute concentration is 1 mol dm-3 or 100 kPa for gases. Eº of the SHE is 0 V."
  • "When aqueous solutions are electrolysed, water can be oxidized to oxygen at the anode and reduced to hydrogen at the cathode.
  • Gº = -nFEº. When Eº is positive, ΔGº is negative indicative of a spontaneous process. When Eº is negative, ΔGº is positive indicative of a non-spontaneous process. When Eº is 0, then ΔGº is 0."
  • "Current, duration of electrolysis and charge on the ion affect the amount of product formed at the electrodes during electrolysis."
  • "Electroplating involves the electrolytic coating of an object with a metallic thin layer."





Organic Chemistry—12 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Types of organic reactions (HL ONLY) 20.1

Nucleophilic Substitution Reactions:

  • "SN1 represents a nucleophilic unimolecular substitution reaction and SN2 represents a nucleophilic bimolecular substitution reaction. SN1 involves a carbocation intermediate. SN2 involves a concerted reaction with a transition state."
  • "For tertiary halogenoalkanes the predominant mechanism is SN1 and for primary halogenoalkanes it is SN2. Both mechanisms occur for secondary halogenoalkanes."
  • "The rate determining step (slow step) in an SN1 reaction depends only on the concentration of the halogenoalkane, rate = k[halogenoalkane]. For SN2, rate = k[halogenoalkane][nucleophile]. SN2 is stereospecific with an inversion of configuration at the carbon."
  • "SN2 reactions are best conducted using aprotic, non-polar solvents and SN1 reactions are best conducted using protic, polar solvents."

Electrophilic Addition Reactions:

  • "An electrophile is an electron-deficient species that can accept electron pairs from a nucleophile. Electrophiles are Lewis acids."
  • "Markovnikov's rule can be applied to predict the major product in electrophilic addition reactions of unsymmetrical alkenes with hydrogen halides and interhalogens. The formation of the major product can be explained in terms of the relative stability of possible carbocations in the reaction mechanism."

Electrophilic Substitution Reactions:

  • "Benzene is the simplest aromatic hydrocarbon compound (or arene) and has a delocalized structure of π bonds around its ring. Each carbon to carbon bond has a bond order of 1.5. Benzene is susceptible to attack by electrophiles."

Reduction Reactions:

  • "Carboxylic acids can be reduced to primary alcohols (via the aldehyde). Ketones can be reduced to secondary alcohols. Typical reducing agents are lithium aluminum hydride (used to reduce carboxylic acids) and sodium borohydride."
Synthetic routes (HL ONLY) 20.2
  • "The synthesis of an organic compound stems from a readily available starting material via a series of discrete steps. Functional group interconversions are the basis of such synthetic routes."
  • "Retro-synthesis of organic compounds."
Stereoisomerism (HL ONLY) 20.3
  • "Stereoisomers are subdivided into two classes—conformational isomers, which interconvert by rotation about a σ bond and configurational isomers that interconvert only by breaking and reforming a bond. Configurational isomers are further subdivided into cis-trans and E/Z isomers and optical isomers."
  • "Cis-trans isomers can occur in alkenes or cycloalkanes (or heteroanalogues) and differ in the positions of atoms (or groups) relative to a reference plane. According to IUPAC, E/Z isomers refer to alkenes of the form R1R2C=CR3R4 (R1 ≠ R2, R3 ≠ R4) where neither R1 nor R2 need be different from R3 or R4."
  • "A chiral carbon is a carbon joined to four different atoms or groups."
  • "An optically active compound can rotate the plane of polarized light as it passes through a solution of the compound. Optical isomers are enantiomers. Enantiomers are non-superimposeable mirror images of each other. Diastereomers are not mirror images of each other."
  • "A racemic mixture (or racemate) is a mixture of two enantiomers in equal amounts and is optically inactive."



Topic #21: Measurement and Analysis—2 Hours for HL Only

Subtopic Subtopic Number IB Points to Understand
Spectroscopic identification of organic compounds (HL ONLY) 21.1
  • "Structural identification of compounds involves several different analytical techniques including IR, 1H NMR and MS."
  • "In a high resolution 1H NMR spectrum, single peaks present in low resolution can split into further clusters of peaks."
  • "The structural technique of single crystal X-ray crystallography can be used to identify the bond lengths and bond angles of crystalline compounds."



Practical Scheme of Work and Assessments

You’ll also need to complete experiments, experimental reports, and assessments as a part of any IB Science course. SL students will have to dedicate 40 hours to the experimental programme assignments and 3 hours for assessments. For HL, students will have to dedicate 60 hours for the experimental programme and 4.5 hours for assessments. 

Here are the activities:

  • Practical work—20 hours for SL and 40 hours for HL
    • In-class opportunities to develop practical and investigative skills (lab work)
    • Work will include things like conducting closed and open inquiries, hands-on experimentation (lab work), and using simulations and modelling
  • Collaborative sciences project—10 hours for both SL and HL
    • Students are separated into groups and must conduct an experiment and write a report.
  • Scientific investigation (internal assessment-IA)—10 hours for both SL and HL
    • A lab project along with a report that counts as 20% of your IB exam scores (written exam counts for the other 80%)
    • This work is also considered part of the final assessment for the course. The 10 required hours include both the ‘practical work’ part of the project (the lab work and experiments you’ll do) and the ‘assessment’ part of the project (the written report you’ll write after completing your lab work and experiments). 



In addition to the practical work for the course, you’ll have a number of assessments for IB Chemistry. The learning objectives for these assessments are as follows:

  • Assessment Objective 1: Demonstrate knowledge of:
    • terminology, facts and concepts
    • skills, techniques and methodologies
  • Assessment Objective 2: Understand and apply knowledge of:
    • terminology and concepts
    • skills, techniques, and methodologies
  • Assessment Objective 3: Analyze, evaluate, and synthesize:
    • Experimental procedures
    • Primary and secondary data
    • Trends, patterns and predictions
  • Assessment Objective 4: Demonstrate the application of skills necessary to carry out insightful and ethical investigations


The external assessments you’ll have to complete are:

  • Paper 1: Divided into two parts/papers—1.5 hours for SL and 2 hours for HL
    • Paper 1A: includes multiple-choice questions to assess experimental skills and techniques 
    • Paper 1B: includes analysis questions to assess experimental skills and techniques 
  • Paper 2—1.5 hours for SL and 2.5 hours for HL
    • includes short-answer and extended-response questions to assess intertwining skills, concepts and understandings


You’ll also have one internal assessment to complete:

  • Scientific investigation (internal assessment-IA)—10 hours for both SL and HL
  • A lab project along with a report that counts as 20% of your IB exam scores (written exam counts for the other 80%)
  • This work is also considered part of the practical work for the course. The 10 hours include both the ‘practical work’ part of the project (the lab work and experiments you’ll do) and the ‘assessment’ part of the project (the written report you’ll write after completing your lab work and experiments). 



Probably shouldn't take selfies with chemicals in your IB Chem class.


What's Next?

Looking for notes and a study guide for IB Chemistry? We have a complete guide to IB Chemistry, a breakdown (so to speak) of what enzymes are and what they do, and specific tips for balancing chemical equations. You can also find out where to buy past IB Chemistry papers here!

Curious about how you can use your chemistry knowledge outside the classroom? Try out these three recipes for slime and see which combination of ingredients has what effect! And if after doing this your kitchen mysteriously comes down with a case of the clogged drains, you'll want to learn how to use muriatic acid safely and effectively to solve the problem.

Are you hoping to squeeze in some extra IB classes? Learn about the IB courses offered online.

Studying for the SAT? Check out our complete guide to the SAT. Taking the SAT in the next month? Check out our guide to cramming.

Not sure where you want to go to college? Check out our guide to finding your target school.



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Dora Seigel

As an SAT/ACT tutor, Dora has guided many students to test prep success. She loves watching students succeed and is committed to helping you get there. Dora received a full-tuition merit based scholarship to University of Southern California. She graduated magna cum laude and scored in the 99th percentile on the ACT. She is also passionate about acting, writing, and photography.

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