Chromatography

Hextable School Science Faculty

Course title: BTEC First Certificate/Diploma in Applied Science

Tutor name: Mr. Riggans

Assignment title: Chemical and physical evidence Ref:

Learner name

Start date: 19/05/08Deadline:

23/05/08

Unit :10Scenario

Scene of crime officers (SOCOs) need to use the correct techniques to search crime scenes and recover valid evidence. They also need to act as expert witnesses in a court of law. In this assignment you will take the role of a forensic scientist, gathering evidence and presenting it to the court. You will find out who has been altering and forging cheques, and describe how other physical data can be used by SOCOs.

Assessment evidence:Unit 10 Grading criteria

P3 produce and follow a realistic and achievable plan to analyse two types of physical and chemical dataM3 describe patterns in physical and chemical data and make connectionsD3 explain patterns in physical and chemical data and make connections

P4 prepare a statement to give evidence in court identifying the techniques used to obtain the evidence and the conclusions from an investigationM4 prepare a statement to give evidence in court describing the techniques they used to obtain evidence and explain the conclusions drawn from an investigationD4 prepare a statement to give evidence in court evaluating the techniques they used to obtain evidence and justify the conclusions drawn in an evaluation

Summary assessor’s feedback

Internal verifier’s comment

Learner’s signature

Task 1 (P3)Complete your investigation into finding out who forged the cheques (using chromatography techniques). Make sure you write down your plan clearly

Task 2 (M3)Describe how the patterns in the results taken from the ink investigation help to draw conclusions

Task 3 (P3/M3/D3)Physical footprints from three suspects were found at the scene of a crime. Describe how a forensic scientist could analyse this evidence and draw conclusions

Task 4 (P4/M4/D4)Write your court statement, giving evidence based on the forgers ink (chromatography) investigation. Identify/evaluate the chromatography techniques used and explain why the conclusions that you as an expert have drawn, correctly identify the accused forger.

Note – to get P3 you must do both task 1 and task 3

Chromatography

1.What are the risks in using the following pieces of equipment?

Beaker

ink

capillary tube

paper clip

2.Set up the equipment as shown

3. PLAN what you will do here (make sure it is a fair test) if you are unsure then read the guidance (on the last page) first.

4. Results Place a labeled photograph or diagram of your results here

6. Table of results

1 2 3 4

Ink name /type Distance traveled by water (mm)

Distance traveled by ink (mm)

Rf value

(column 3 / column 2)

Forgers ink

Conclusion - Describe and explain your results hereWho is the forger? How do you know?

Evaluation

Identify and describe a weakness in your method

Suggest improvements you would make to your method if you were to do it again

Information for plan:

Place a small dot of ink above the level of the water.Repeat with the different inks.

Use the same amount of ink and the same volume of water

Leave each strip for the same amount of time (10 minutes)

For each ink you do you need to measure:

the distance traveled by the water the distance traveled by the ink