What we cover
Six topics, two big ideas: the IB Chemistry syllabus
The guide sorts chemistry under two ideas: structure, the nature of matter, and reactivity, how and why reactions happen. HL adds depth inside the same six topics.
SL is planned as a 150-hour course and HL as a 240-hour one; 40 and 60 of those hours cover lab practicals, the investigation and the collaborative sciences project.
Structure 1: the particulate nature of matter
SL 17 h, HL 21 hAtoms, electron configurations, the mole and ideal gases. Mole work feeds every later topic, and marks slip on units, significant figures and converting between mass, volume and concentration.
- Electron configurations
- The mole and molar concentration
- The ideal gas equation
Structure 2: models of bonding and structure
SL 20 h, HL 30 hIonic, covalent and metallic models, VSEPR shapes, intermolecular forces and polymers. HL adds formal charge, sigma and pi bonds and hybridisation. A polar bond is often confused with a polar molecule.
- VSEPR shapes
- Intermolecular forces
- Addition and condensation polymers
Structure 3: classification of matter
SL 16 h, HL 31 hPeriodic trends, oxidation states, functional groups and IUPAC names. At HL it also holds transition elements, stereoisomers and spectroscopy: mass spectra, infrared and 1H NMR.
- Periodic trends
- IUPAC naming
- IR and 1H NMR at HL
Reactivity 1: what drives chemical reactions?
SL 12 h, HL 22 hCalorimetry, Hess's law, bond enthalpies and fuels. HL adds Born-Haber cycles, entropy and Gibbs energy. Heat-loss assumptions in calorimetry cost marks on both papers.
- Calorimetry
- Hess's law
- Gibbs energy at HL
Reactivity 2: how much, how fast and how far?
SL 21 h, HL 31 hYield and atom economy, rates and collision theory, equilibrium and Le Châtelier's principle. HL adds rate equations, the Arrhenius equation and calculations with K and Q. Graph reading decides many marks.
- Limiting reactant
- Rate equations at HL
- The equilibrium constant
Reactivity 3: mechanisms of chemical change
SL 24 h, HL 45 hProton transfer, electron transfer, radicals, nucleophiles and electrophiles. The largest HL topic adds pKa, buffers, electrode potentials and SN1 and SN2. Curly arrows lose marks when drawn from the wrong atom.
- pH and buffers
- Redox and electrochemical cells
- Organic mechanisms
Tools and the inquiry process
SL and HLExperimental techniques, technology and mathematics, used to design, collect and process data, conclude and evaluate. These skills carry Paper 1B and shape the investigation.
- Uncertainty and error
- Graphs and gradients
- Planning a method