# Practical and Investigative Chemistry

> IB Chemistry SL · IB SL Chemistry
> Source: https://www.owlsprep.com/study/ib-chemistry-sl-u7-overview/
> Weight: n/a

This unit covers all core practical and inquiry skills required for IB Chemistry SL, including experimental design, data handling, analysis, and collaborative work for internal assessment.

**Prerequisites:** Foundational knowledge of all IB Chemistry SL core topics from units 1–6

## Learning objectives

- Design valid, controlled chemistry experiments aligned with testable research questions
- Process and present raw experimental data correctly with appropriate significant figures and uncertainty
- Evaluate experimental results, identify sources of error, and propose targeted, realistic improvements
- Plan and execute collaborative scientific inquiries following IB Chemistry assessment standards

## Unit at a glance

This unit builds the scientific inquiry skills you need to complete your IB Chemistry SL internal assessment (IA) and answer practical questions on the final exam. The learning path progresses from planning an experiment through to final evaluation, mirroring the full process of real scientific investigation.

Each sub-topic breaks down a key stage of the practical process, with specific guidance aligned to IB marking criteria. By the end of the unit, you will be able to independently plan and report on a full chemistry investigation.

Core sub-topics in this unit:
- [Experimental design and procedure](https://www.owlsprep.com/study/ib-chemistry-sl-u7-experimental-design-and-procedure/) — Learn how to write research questions, control variables, and plan safe, valid experimental procedures.
- [Data collection and processing](https://www.owlsprep.com/study/ib-chemistry-sl-u7-data-collection-and-processing/) — Master raw data recording, significant figures, uncertainty calculation, and graphical data presentation.
- [Results analysis and evaluation](https://www.owlsprep.com/study/ib-chemistry-sl-u7-results-analysis-and-evaluation/) — Practice analyzing results, identifying error sources, and evaluating experimental validity with targeted improvements.
- [Collaborative scientific inquiry](https://www.owlsprep.com/study/ib-chemistry-sl-u7-collaborative-scientific-inquiry/) — Develop skills for planning and contributing to group scientific investigations aligned with IB requirements.

## Common pitfalls

- **Wrong:** Reporting raw data with incorrect significant figures that do not match instrument precision.
  - Why it fails: This leads to unnecessary lost marks in both practical exams and internal assessment.
  - Correct: Always match significant figures to the smallest division of the measuring instrument used.
- **Wrong:** Using generic error claims like 'human error' in evaluations without specific context.
  - Why it fails: IB requires demonstration of critical thinking, so vague claims do not earn evaluation marks.
  - Correct: Identify specific systematic or random errors and explain how they impacted your final result.
- **Wrong:** Forgetting to include a full risk assessment when designing your experiment.
  - Why it fails: Safety is assessed in practical work, and missing this section can invalidate your investigation.
  - Correct: Always document hazards, risks, and safety mitigations for all procedures and chemicals.

## Cheatsheet

| Concept/Skill | Key Rule/Formula |
| --- | --- |
| Absolute uncertainty of a measuring instrument | Half the smallest division of the instrument |
| Significant figures for processed data | Match to the least precise measurement used in calculation |
| Percentage uncertainty calculation | $\% \Delta = \frac{\text{absolute uncertainty}}{\text{measured value}} \times 100$ |
| Valid experimental design | One independent variable changed, all other variables controlled |
| Good evaluation requirement | Specific error → impact on result → realistic improvement |
| IA Criterion Weighting | Planning 20%, Data Collection 30%, Analysis 25%, Evaluation 25% |

## What's next

Begin your learning of this unit with the first sub-topic on experimental design, which forms the foundation of all practical chemistry work for IB. Once you complete all four sub-topics here, you will be ready to move on to final exam preparation for your IB Chemistry SL assessment.

- [Experimental design and procedure](https://www.owlsprep.com/study/ib-chemistry-sl-u7-experimental-design-and-procedure/)
- [Data collection and processing](https://www.owlsprep.com/study/ib-chemistry-sl-u7-data-collection-and-processing/)
- [Results analysis and evaluation](https://www.owlsprep.com/study/ib-chemistry-sl-u7-results-analysis-and-evaluation/)

---

From [OwlsPrep](https://www.owlsprep.com) — free study guides for A-Level, IB, AP and IGCSE, written against the official syllabus. Canonical page: https://www.owlsprep.com/study/ib-chemistry-sl-u7-overview/