Internal assessment requirements
IB Chemistry HLΒ· Unit 7: Practical and Investigative SkillsΒ· 15 min read
1. Overview and Weightingβ β ββββ± 3 min
The IB Chemistry HL internal assessment is a mandatory, student-led research project marked internally by your teacher and externally moderated by IB examiners. The total score from all six criteria contributes exactly 20% of your final course grade.
Assessment Criterion | Maximum Marks |
|---|---|
Personal Engagement | 2 |
Exploration | 6 |
Analysis | 6 |
Evaluation | 6 |
Conclusion | 3 |
Communication | 4 |
Calculate the total mark for an IA with the following scores: Personal Engagement (2), Exploration (5), Analysis (5), Evaluation (4), Conclusion (3), Communication (4).
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Sum the marks for all six criteria to get the total out of 27:
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2. Assessment Criterion Breakdownβ β β βββ± 5 min
Each criterion assesses a distinct aspect of your investigation, and understanding what examiners look for in each is critical to scoring full marks. Personal Engagement assesses your personal input and motivation, while Exploration checks that your research question is focused and methodologically sound.
Personal Engagement
The criterion that assesses your independent input, personal motivation, and adaptation of the investigation to your own interests.
Example:
Tying an investigation of reaction rate to your interest in home brewing.
How do you modify a generic research question 'How does temperature affect rate of reaction' to meet the Personal Engagement criterion?
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Step 1: Add a personal context that motivated your investigation to show independent interest.
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Step 2: Refine the question to add specific variables and a focused system, instead of a generic prompt.
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Final modified question: 'How does temperature between 20Β°C and 70Β°C affect the activation energy of yeast fermentation, motivated by my home brewing hobby?'
3. Report Structure and Administrative Rulesβ β β βββ± 4 min
Non-compliance with administrative rules is a common cause of unexpected lost marks, even for strong investigations. IB expects a standard report structure and enforces a strict word limit.
Title page with research question, candidate number, and word count
Introduction with background and motivation
Methodology for data collection
Data analysis and processing
Evaluation of methodology and results
Conclusion linking findings to the research question
Bibliography and citations
Your main body is 3250 words. How do you reduce the word count without losing key content?
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Step 1: Move full tables of raw experimental data to an appendix (raw data does not count towards the word limit).
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Step 2: Cut redundant background chemistry content that is not directly relevant to your specific research question. For example, you do not need a full page explanation of collision theory for a rate investigation.
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Step 3: Remove repetitive descriptions of individual trials. You can state 'each measurement was repeated 3 times to reduce random error' instead of describing each trial separately.
4. Authenticity and Academic Integrityβ β ββββ± 3 min
IB takes academic integrity for the IA extremely seriously. Plagiarism, collusion, or copying work from other sources results in severe penalties, including a grade of 0 for the entire IA component.
You find an existing investigation online that tests the same research question you want to explore. Is it acceptable to use their methodology as a starting point?
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Step 1: It is acceptable to use an existing methodology as a starting point, but you must modify it to show your own independent input.
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Step 2: Cite the original source clearly in your bibliography, and document all changes you made to the methodology for your investigation.
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Step 3: All data analysis, processing, and evaluation must be your own original work, even if you use an existing methodology or public data set.
5. Common Pitfalls
Wrong move:
Exceeding the 3000 word limit for the main body of the report
Why:
IB examiners do not mark any content beyond the word limit, so you will lose marks for any cut-off text
Correct move:
Move non-essential raw data and supporting calculations to appendices, cut redundant background content, and trim verbose phrasing to get under the limit
Wrong move:
Failing to cite all sources, including data sets for secondary IAs
Why:
This counts as plagiarism, which leads to academic integrity penalties and a potential 0 for the IA
Correct move:
Use a consistent citation style for all sources, including websites, data sets, and existing investigations you referenced
Wrong move:
Submitting a vague, unfocused research question
Why:
Unspecific questions lose marks in the Exploration criterion, as they show a lack of planning
Correct move:
Refine your question to include specific variables, their range, and the exact chemical system you are testing
Wrong move:
Only discussing random measurement error in your evaluation, ignoring systematic error
Why:
Evaluation requires you to discuss significant methodological limitations, so this limits your score to 3 or lower out of 6
Correct move:
Identify 2-3 significant systematic errors relevant to your investigation and explain how they impact your results
Wrong move:
Copying a procedure directly from a lab manual or website with no modifications
Why:
This loses marks in Personal Engagement and Exploration, as it shows no independent input
Correct move:
Modify the procedure to test a different variable range, use a new measurement method, or adapt it to answer your own specific question
6. Quick Reference Cheatsheet
Requirement | Official Rule |
|---|---|
Total course weight | 20% of final IB Chemistry HL grade |
Total maximum marks | 27 |
Maximum word count (main body) | 3000 words |
Personal Engagement | 2 marks |
Exploration | 6 marks |
Analysis | 6 marks |
Evaluation | 6 marks |
Conclusion | 3 marks |
Communication | 4 marks |
Primary/secondary data | Both are allowed |
All sources must be cited | Required for academic integrity |
7. Frequently Asked
Does the 3000 word limit include appendices or citations?
No, the limit only applies to the main body of the report. Raw data in appendices and citations/bibliography are excluded from the word count.
Am I allowed to do a secondary-data IA instead of a practical investigation?
Yes, IB allows secondary-data IAs as long as you use raw, publicly available data and conduct original analysis. All the same assessment criteria apply.
When this came up on past exams
AI-estimated based on syllabus patterns β cross-check with official past papers for accuracy. Use only as revision-focus signals.
- All Β· N/A (Coursework)
Mandatory 20% weighted component
Going deeper
What's Next
Understanding the core requirements of the IA is the first step to designing a high-scoring investigation. Next, you will develop a focused research question aligned to the assessment criteria, plan your methodology and data collection, then write each section of your report to match examiner expectations. Starting early and leaving time for revisions based on teacher feedback is critical, as this allows you to fix gaps before submission. A strong IA combines solid chemistry with clear communication and personal input, so aligning every section of your work to the markscheme will help you secure the highest possible marks.