At a glance
- Current guide
- First assessed May 2025
- Content
- Structure 1 to 3, Reactivity 1 to 3
- Paper 1
- 1A multiple choice + 1B data-based, 36%
- Paper 2
- 44%
- Internal assessment
- Scientific investigation, 20%
IB Chemistry assessment, SL and HL
| Component | SL | HL | Weighting |
|---|---|---|---|
| Paper 1A: multiple choice | 30 questions, 30 marks | 40 questions, 40 marks | 36% with Paper 1B |
| Paper 1B: data-based questions on experimental work | 25 marks | 35 marks | 36% with Paper 1A |
| Paper 1 total time | 1 h 30 min | 2 h | |
| Paper 2: short answer and extended response | 1 h 30 min | 2 h 30 min | 44% |
| Scientific investigation (IA) | About 10 hours, 24 marks | About 10 hours, 24 marks | 20% |
Papers 1A and 1B are sat together in one sitting. A chemistry data booklet is provided in the exams.
How the content is organised
| Strand | Topics |
|---|---|
| Structure 1 | Models of the particulate nature of matter: atoms, electron configuration, the mole, ideal gases |
| Structure 2 | Models of bonding and structure: ionic, covalent, metallic bonding, intermolecular forces |
| Structure 3 | Classification of matter: the periodic table, functional groups and organic nomenclature |
| Reactivity 1 | What drives chemical reactions: enthalpy, energy cycles, entropy and spontaneity (HL) |
| Reactivity 2 | How much, how fast and how far: stoichiometry, kinetics, equilibrium |
| Reactivity 3 | Mechanisms of chemical change: acids and bases, redox, electron sharing and substitution reactions |
Where IB Chemistry marks are lost
- Calculations without units or with the wrong significant figures. Moles, enthalpy and equilibrium questions punish loose working.
- Slow multiple choice. Paper 1A rewards quick, confident recall and estimation; students who work every option out in full run short of time for 1B.
- Weak explanation of trends. Ionisation energy or boiling-point trends need the structural reason, not just the pattern.
- Organic mechanisms at HL. Curly arrows must start from a lone pair or a bond and end at an atom; sloppy arrows score zero.
- Paper 1B data questions. Students who have not done much practical work struggle to interpret uncertainties, graphs and methods.
How one-to-one Chemistry lessons work
Tutors who teach IB Chemistry use the shared whiteboard for what chemistry needs most: structures, energy cycles, mechanisms and step-by-step calculations. A typical lesson reviews the current school topic, works through two or three quantitative problems with the student explaining each step, then sets past-paper questions marked against the markscheme. The tutor keeps a log of question types the student drops marks on and returns to them until they hold.
For the scientific investigation, the tutor helps the student find a measurable research question, think through variables and uncertainties, and understand data processing. The write-up must be the student's own work.
A common trap with new content
Because the guide reorganised topics, some classic past-paper questions now sit in different places, and some content (such as the old options) is no longer examined. Check practice questions against the current guide before spending time on them.
Common questions
Is IB Chemistry HL hard?
It is one of the more demanding HL sciences, mainly because of the quantitative load and the organic chemistry. Students with secure algebra and steady weekly revision usually manage it well.
What subjects pair with IB Chemistry for medicine?
Many medical schools ask for HL Chemistry plus HL Biology, but requirements vary by university and country. Check each medical school's published requirements.
Is there still an option paper?
No. Since May 2025 the options and Paper 3 have been removed. Assessment is Paper 1 (1A and 1B), Paper 2 and the scientific investigation.
Can a tutor help with the Chemistry IA?
Yes, within the IB's rules: choosing a question, planning, discussing data processing and uncertainty, and general feedback. The student does the investigation and writes the report.
How much do IB Chemistry lessons cost with LiveTutor?
$15 a lesson, the same rate for every subject and level, on a weekly plan of 1 to 5 lessons billed monthly. Lessons are 60 minutes, one to one and online, and the first is free.
Sources
Dates and figures on this page come from these official and published sources. Always confirm deadlines on the official page before acting on them.