Topic I.3 · HL only
Concluding and evaluating: notes and practice questions
Summary
- This topic covers the application of concluding and evaluating skills to the broader and deeper content of the HL chemistry syllabus.
- Students are expected to demonstrate a more sophisticated understanding of the impact of uncertainties on conclusions.
- A higher level of critical analysis is required when evaluating hypotheses and methodological weaknesses.
- Explanations of realistic and relevant improvements should reflect the complexity of HL investigations.
How it is examined
Paper 1B, usually the last parts of a question. May 2025 HL Paper 1B TZ1 asked for two reasons for a difference between two students' timings, capped at 2 marks with a long list of acceptable answers and an explicit list of rejects. Another part asked for an error plus how to reduce or eliminate it, marked as a paired Error/Reduce alternative worth 2 marks: the improvement mark is tied to the error named, so a vague error kills both marks. Command terms are `Suggest`, `Evaluate`, `Explain` and `Discuss`. Tariff 1 to 3 marks.
Key ideas
- Interpret processed data and analysis to draw and justify conclusions.
- Compare the outcomes of an investigation to the accepted scientific context.
- Relate the outcomes of an investigation to the stated research question or hypothesis.
- Discuss the impact of uncertainties on the conclusions.
Guiding questions
- None given.
Linking questions
- Reactivity 1.1 Why do calorimetry experiments typically measure a smaller change in temperature than is expected from theoretical values?
- Reactivity 2.1 What errors may cause the experimental yield to be i) higher and ii) lower than the theoretical yield?
- Reactivity 2.2 How can graphs provide evidence of systematic and random error?
Practice questions
0 questionsNo question on this page matches those filters. Try another difficulty or paper.
Every Concluding and evaluating question, marked for you
Every answer is marked mark by mark, IB-style, and the AI tutor helps when you are stuck.
Where marks are lost
- Reaching for "human error" or "only one trial." A source of error has to be a specific step in the method, not a general apology for the result.
- Joining the dots instead of drawing a curve.
- Naming a chemical instead of the property that distinguishes it, or vice versa. Answering with the nearest fact that comes to mind rather than the fact the command term and stem jointly ask for is a recurring way to answer a question that was not, quite, the one asked.
