To complete a practical investigation linked to 12.4 Separation and Purification and develop IGCSE practical skills in observation, measurement, recording, analysis and evaluation.
| Possible hazard | Safety precaution | Emergency response |
|---|---|---|
| Chemicals may irritate skin or eyes. | Wear eye protection; avoid direct contact; use small quantities. | Rinse affected area with plenty of water and inform the teacher. |
| Glassware, hot apparatus or flames may cause injury. | Handle apparatus carefully; use test-tube holders; keep bags away from benches. | Report breakages, burns or spills immediately. |
| Stage | Substance collected | Observation |
|---|---|---|
| After filtration | ||
| After evaporation/crystallisation |
Additional observations:
| Claim: What happened? | Evidence: What data/observations support this? | Reasoning: What chemistry explains it? |
|---|---|---|
Explain how the mixture was separated and name each technique used.
Identify one source of error and one improvement to the method.
| Source of error | Improvement |
|---|---|
Suggest how you could check whether the salt crystals are pure.
| Criterion | Marks |
|---|---|
| Planning & Organisation | 5 |
| Data Collection & Observations | 5 |
| Processing & Analysis | 10 |
| Evaluation & Improvements | 5 |
| Conclusion | 5 |
| Total | 30 |
Check that your name, class, date and responses are complete before submitting.