Contents |
Introduction | 4 |
Important note: Health and safety disclaimer | 4 |
Curriculum links | 4 |
1. The nature of forensic science | 6 |
The scientist as an expert witness | 6 |
How reliable is forensic evidence? | 7 |
Find out more | 9 |
Useful web links | 9 |
Forensic rulers | 9 |
2. Lights on or off? | 11 |
Forensic focus | 11 |
Activity: Performing a lamp examination | 15 |
Activity: The role of inert gas in protecting the filament | 16 |
Find out more 18Useful web links | 18 |
3. Hidden numbers | 19 |
Forensic focus | 19 |
Activity: Restoring serial numbers by acid etching | 21 |
Activity: Stamped serial number restoration by heat treatment | 23 |
Find out more | 24 |
Useful web links | 24 |
4. Glass fracture patterns | 25 |
Forensic focus | 25 |
Activity: Impact testing | 28 |
Find out more | 29 |
5. A spectrum of possibilities | 30 |
Forensic focus | 30 |
Activity: Building a Lego spectrophotometer | 34 |
Activity: Analysis of food colourings | 38 |
Infrared spectroscopy | 39 |
Find out more | 40 |
6. Thin-layer chromatography | 41 |
Forensic focus | 41 |
Activity: Making sample applicators | 43 |
Activity: Making TLC plates | 44 |
Activity: Applying samples, developing the TLC plates and visualisation | 45 |
Find out more | 46 |
7. Poisons, medicines and drugs | 47 |
Forensic focus | 47 |
Activity: Spot tests | 54 |
Activity: Thin-layer chromatography with common medicines | 55 |
Activity: Making oil of wintergreen | 57 |
Activity: Extracting caffeine from tea | 58 |
Find out more | 59 |
8. Don't play with matches | 60 |
Forensic focus | 60 |
Activity: Using steam distillation to collect ignitable liquids | 63 |
Activity: Analysing the distillate by thin-layer chromatography | 65 |
Find out more | 67 |