Current syllabus · first assessment 2025

IB · Chemistry · HL

IB Chemistry HL

Study IB Chemistry HL through connected ideas about structure, reactivity and chemical change.

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Subject overview

IB Chemistry HL at a glance

Follow the live HL knowledge tree from Structure and Reactivity to topics and learning objectives.

6
syllabus units
21
mapped topics
7
study tools

What you study in IB Chemistry HL

IB Chemistry HL connects microscopic models with the observable behaviour of matter and chemical reactions.

Use the syllabus map to move from a structure or reactivity idea to Concepts, Mastery or Question Bank.

Explore the IB Chemistry HL syllabus

Follow the live HL knowledge tree from Structure and Reactivity to topics and learning objectives.

IB Chemistry HL exam skills

Practise the command terms, data handling and extended reasoning used across IB assessment.

  • Follow command termsMatch the depth and structure of the response to the exact instruction.
  • Use data as evidenceRead units and uncertainty, identify patterns and support conclusions with values.
  • Build mark-efficient explanationsLink cause, evidence and subject vocabulary without repeating the prompt.

SourceCurrent IB subject guide and assessment objectives.

Know the exam

IB Chemistry HL assessment

The HL course combines two external papers worth 80% of the final grade with a scientific investigation worth 20%.

Paper / componentQuestionsTime% of grade
Paper 1See the current paper specification75 marksPaper 1A multiple-choice questions and Paper 1B data-based or experimental-work questions.2 hours36%
Paper 2See the current paper specification90 marksShort-answer and extended-response questions across the course.2 hours 30 minutes44%
Scientific investigationSee the current paper specification24 marksOne internally assessed investigation, externally moderated by the IB.10 hours20%

SourceIB Chemistry guide · First assessment 2025

Paper 1 contributes 36%, Paper 2 contributes 44%, and the scientific investigation contributes 20% of the final subject grade.

The course uses Structure and Reactivity to connect models of matter with chemical change and measurable evidence.

HL includes additional syllabus content and greater depth across Structure and Reactivity, with longer external papers.

Start from an HL objective, review its Concept explanation, then use Mastery and Question Bank resources to practise that exact scope.