How Many IB Chemistry Papers Are There?

Just starting your IB Diploma (opens in a new tab)? You’re probably asking, “What is IB Chemistry and how is it structured?” Knowing the exam format is the first step to planning an effective revision strategy.

So, what's the simple answer for the exams starting in 2025? 

There are 2 external exam papers for both Standard Level (SL) and Higher Level (HL) IB Chemistry, plus your Internal Assessment (IA). Many students also wonder, "Is IB Chemistry Hard?", and knowing what's coming can make it feel much more manageable.

Important note: The old "Paper 3" and the "Option Topics" have been removed from the syllabus. Any resource that mentions three papers is outdated!

Let's break it all down so you know exactly what you're preparing for.

Quick answer – IB Chemistry exam overview

Both SL and HL students are assessed on 2 external exam papers and 1 Internal Assessment.

• Paper 1: Multiple Choice & Data-Based Questions

• Paper 2: Short and Extended Response Questions

• Internal Assessment (IA): A scientific investigation

The key difference? HL papers are longer, cover more content, and have more marks available.

Here's a quick comparison table to show you the main differences:

IB Chemistry paper structure – SL vs HL

Now let's dive deeper into what each paper actually involves. Understanding the format of each paper will help you tailor your revision approach perfectly!

To see exactly what's covered, you can review our IB Chemistry Topics: Full List article.

Paper 1 – Multiple choice & data analysis

Paper 1 checks two things: your knowledge recall and your analysis skills. It’s split into two parts (1A and 1B), completed in one sitting.

• Format: Multiple-choice and data-based questions

• Calculators: Allowed

• Data booklet: Provided

SL Students:

• Total time: 1 hour 30 minutes

• Total marks: 55

• Weighting: 36%

• Paper 1A: 30 multiple-choice questions on core topics.

• Paper 1B: Data-based questions where you'll interpret unfamiliar graphs and experiments.

HL Students:

• Total time: 2 hours

• Total marks: 75

• Weighting: 36%

• Paper 1A: 40 multiple-choice questions covering core and HL extension topics.

• Paper 1B: More complex data-based and experimental questions.

The multiple-choice questions often start easier and get progressively harder. You'll face everything from simple recall questions to application-based scenarios.

Paper 2 – Short and extended response

This is often considered the most important paper as it carries the highest weighting (44%) for both levels.

• Format: Mix of short-answer and extended-response questions

• Calculators: Allowed

• Data booklet: Provided

Paper 2 tests your ability to:

• Perform multi-step calculations

• Explain complex chemical concepts in detail

• Apply your knowledge to new scenarios

• Draw and interpret chemical structures

SL Students:

• Time: 1 hour 30 minutes

• Marks: 50

• Weighting: 44%

• Focuses entirely on the core syllabus content.

HL Students:

• Time: 2 hours 30 minutes

• Marks: 90

• Weighting: 44%

• Includes questions on both core and HL extension material, often linking multiple topics together.

The questions range from straightforward calculations to complex explanations requiring detailed chemical understanding.

Internal Assessment (IA) and final grade weighting

Your IA is worth a huge 20% of your final grade for both SL and HL. That's one-fifth of your entire IB score riding on a single project, so it's vital to give it the attention it deserves!

The IA is an individual investigation of up to 3,000 words. You’ll design an experiment, collect data, and present your findings in a formal report. Your report is marked against four key criteria:

• Research design: How well you plan your investigation.

• Data analysis: How you process and present your data.

• Conclusion: How you interpret your results in a scientific context.

• Evaluation: How you reflect on your methodology and suggest improvements.

The IA is your chance to shine as a scientist, showcasing your practical chemistry skills and scientific thinking. Many students enjoy it because you can explore a topic you're curious about and have time to perfect your work outside of exam pressure.

Why understanding paper structure matters

Knowing the structure of each paper is absolutely essential for effective revision. Here's why:

Targeted practice: 

• You can focus your efforts on the specific skills each paper tests. 

• For Paper 1, you need to practise both your MCQ speed and your data analysis skills.

• For Paper 2, it's all about mastering long-form answers and calculation drills.

• Using Flashcards is great for quick recall.

• Tackling topic-specific Exam Questions will help you master question formats.

Time management: 

• Understanding the timing and mark allocation helps you:

  • Pace yourself during exams.

  • Just as importantly, allocate your revision time appropriately.

• The best way to simulate real exam conditions is by working through full-length Mock Exams.

Confidence building: 

• Familiarity with the exam formats reduces anxiety and helps you feel more prepared and in control on test day.

• Reviewing our Practice Papers is the perfect way to do this.

Strategic revision:

• You can prioritise your weakest areas based on paper weightings. Paper 2 carries the most marks (44%), so it deserves significant attention!

Save My Exams offers targeted practice materials for each paper type, including practice papers and detailed mark schemes that align with IB requirements.

Frequently asked questions

How many IB Chemistry papers are there at HL vs SL?

Both HL and SL students sit exactly 2 exam papers plus complete one Internal Assessment. The difference is in the length, difficulty, and content of these papers, not the number.

How long is each IB Chemistry paper?

SL Timings:

• Paper 1: 1 hour 30 minutes

• Paper 2: 1 hour 30 minutes

HL Timings:

• Paper 1: 2 hours

• Paper 2: 2 hours 30 minutes

What percentage of the grade does each paper count for?

For both SL and HL:

• Paper 1: 36%

• Paper 2: 44%

• IA: 20%

Is the Internal Assessment as important as the exam papers?

Absolutely. At 20%, the IA is a significant part of your grade. A strong IA can be the key to hitting a higher grade boundary, so give it the attention it deserves!

What's the hardest IB Chemistry paper?

This is subjective, but many students find Paper 2 the most challenging due to its length and the depth of explanation required. The data-based questions in Paper 1B can also be tricky if you're not used to interpreting unfamiliar scientific results.

The key is practice - the more familiar you become with each paper's format, the more manageable they'll feel!

For a teacher's take on this, read our article: Is IB Chemistry Hard?: A Teacher’s Perspective.

Final thoughts

To sum it up: for your IB Chemistry exams, you're preparing for 2 main papers and one Internal Assessment.

Knowing the format of each component is your first step to success. Now you can use this knowledge to build a powerful study plan. For a complete guide on how to do this, check out our article on How To Revise IB Chemistry.

Ready to start practicing? Save My Exams has all the comprehensive IB Chemistry resources you need:

With the right preparation, you'll be ready to tackle those papers with confidence!

Good luck with your IB Chemistry journey - you've got this

References

Official IB DP Chemistry webpage (opens in a new tab)